fruit and vegetable intake

Fruit and vegetable intake: Guidelines vs reality

The Australian Dietary Guidelines recommend an average minimum daily intake of 5 serves of vegetables (including legumes) and 2 serves of fruit to prevent chronic disease.

Nutrients in fruits and vegetables

Most fruits, vegetables and legumes are good source of carbohydrate (sugar and/or starch) and fibre. They also water and contain micronutrients, such as vitamins, minerals and phytochemicals. Most are low in fat with few exceptions (olives, avocados, coconuts).

Legumes are a decent source of protein and some contain non-haem iron, which is less bioavailable than haem iron from animal sources. Legumes also contain phytates which act as antioxidants but bind to minerals, affecting their absorption. Cooking and storing methods can affect the nutritional content of fruits and vegetables, but that’s another topic for another time.

Why do we need fruits and vegetables?

Most healthy and long-living populations around the world have something in common a diet based on fresh vegetables and fruits. The pharmaceutical industry has tried to isolate individual nutrients and pack them into pills, but it is clear that the biggest benefits come from eating whole foods. It has been postulated that some positive health effects are due to hormesis (favourable response to a low dose of an otherwise harmful compound).

There is evidence that vegetable consumption decreases the risk of coronary heart disease and stroke. Vegetables may also prevent weight gain and decrease risk of various cancers. The consumption of legumes is associated with reduced risk of colorectal cancer, and, in the case of soy, reduced total and LDL-cholesterol (1).

Consuming fruits may also decrease risk of coronary heart disease and stroke. Fruit intake is also associated with a reduced risk of obesity, weight gain and oral and nasopharyngeal cancer (1).

What is the recommended fruit and vegetable intake?

The number of serves per day recommended in the Australian Dietary Guidelines (1) vary according to gender, age and life stage.

Recommended number of serves per day
Age (years) Vegetables and legume/beans Fruit
Boys 2–3 2 ½ 1
4–8 4 ½ 1 ½
9–11 5 2
12–13 5 ½ 2
14–18 5 ½ 2
Men 19–50 6 2
51–70 5 ½ 2
70+ 5 2
Girls 2–3 2 ½ 1
4–8 4 ½ 1 ½
9–11 5 2
12–13 5 2
14–18 5 2
Pregnant (up to 18 years) 5 2
Breastfeeding (up to 18 years) 5 ½ 2
Women 19–50 5 2
51–70 5 2
70+ 5 2
Pregnant (19–50 years) 5 2
Breastfeeding (19–50 years) 7 ½ 2

What is a serve?

Below is the definition of a serve of vegetables/fruit according to the Australian Dietary Guidelines (1). My philosophy is: when in doubt, eat more vegetables.

Vegetables

One serve = 75g, e.g.

  • ½ cup of cooked vegetables or legumes
  • 1 cup of raw vegetables
  • ½ medium potato or equivalent of sweet potato, taro, sweet corn or cassava
  • 1 medium tomato

Fruit

One serve = 150g, e.g.

  • 1 apple, banana, orange or pear
  • 2 apricots, kiwis or plums
  • 1 cup diced fruit, berries, grapes, etc.

Note that the type of vegetables and fruits that you should eat depend on your individual carbohydrate tolerance, goals and health conditions.

How many people are eating the recommended amount?

The short answer is: very few. According to the latest National Health Survey: First Results, 2014-15 (2, 3), most Australians do not meet the guidelines. Below are the percentages of people who did meet their target fruit and vegetable intake:

Vegetables

  • 7% of adults (3.8% males, 10.2% females)
  • 5.4% of children (4.3% males, 6.3% females)

Fruit

  • 49.8% of adults (44.0% males, 55.4% females)
  • 68.1% of children (65.0% males, 71.8% females)

The age groups less likely to meet vegetable and fruit intake are children 12-18 and adults 18-24 years old. Conversely, males 75+ years old, females 65-74 years old and children 2-3 years old were the population groups whose intake were closer to their target.

The following graphs show the proportion of adults having X number of serves of vegetables/fruit per day (data from 2).

The following graphs show the proportion of children having X number of serves of vegetables/fruit per day (data from 3).

Recommendations

  • Fill at least half of your plate with vegetables
  • Because different plants contain different nutrients, it is important to vary your intake
  • Eat fruits and vegetables in season: they are cheaper, have better flavour and nutrient content and are more likely to be local
  • Listen to your body to determine if particular foods cause you issues. For example, many fruits and vegetables are sources of FODMAPs, so you might have to limit their intake if you have any symptoms. Work with a dietitian if you need help.
  • If you’re struggling to eat more vegetables here are some ideas:
    • Throw some spinach, kale and/or avocado into your smoothies
    • If you have a juicer that keeps the fibre, use beetroot, carrot, celery and/or cucumber in your juices
    • Add vegetables to your soups, stews, curries, pasta sauce and even desserts (carrots, beetroot, beetroot and sweet potato are common addition to cakes)
    • Use vegetable sticks instead of crackers to eat dips
    • Serve pasta sauce and stews on vegetables instead of pasta or rice
    • Use other vegetables besides potatoes for mash, for example cauliflower, parsnips, celeriac, turnips, sweet potato, pumpkin (or a combination)
    • Add greens to your regular mash
    • Visit the recipe section for inspiration

References

  1. National Health and Medical Research Council. Australian Dietary Guidelines. Canberra: National Health and Medical Research Council; 2013.
  2. Australian Bureau of Statistics 2015, National Health Survey: First Results, 2014-15, ‘Table 12: Daily intake of fruit and vegetables – Australia’, data cube: Excel spreadsheet, cat. no. 4364055001DO012_20142015, viewed 8 November 2018, http://www.abs.gov.au/ausstats/subscriber.nsf/log?openagent&4364055001do012_20142015.xls&4364.0.55.001&Data%20Cubes&21142A5792B57B5BCA257F150009FABA&0&2014-15&08.12.2015&Latest
  3. Australian Bureau of Statistics 2015, National Health Survey: First Results, 2014-15, ‘Table 17: Children’s daily intake of fruit and vegetables and main type of milk consumed – Australia’, data cube: Excel spreadsheet, cat. no. 4364055001DO017_20142015, viewed 8 November 2018, http://www.abs.gov.au/ausstats/subscriber.nsf/log?openagent&4364055001do017_20142015.xls&4364.0.55.001&Data%20Cubes&F2CCDDF4D775330CCA257F150009FBBD&0&2014-15&08.12.2015&Latest

[Photo by ja ma on Unsplash]

alcohol and health

Alcohol and health: To drink or not to drink

With the end of the year almost here, most of us have social events to attend, which in many cases means increased alcohol consumption. If you wonder what’s the relationship between alcohol and health, read on.

Alcohol, a drug and a nutrient

Alcohol is one of the most prevalent socially accepted drugs. It is also a nutrient, in the sense that it contributes to energy intake. Each gram of alcohol contributes 7 kilocalories (29.3 kilojoules) per gram. Compare this to 4 kilocalories (16.7 kilojoules) per gram of carbohydrate or protein and 9 kilocalories (37.7 kilojoules) per gram of fat.

To put these numbers into perspective, a standard drink is a volume that contains 10 grams (12.5ml) of alcohol. This equals to 70 kilocalories or 293 kilojoules just from the alcohol, to which you should add calories from other macronutrients (e.g. sugar) present on the drink. Also note that regular-sized cans/bottles of beer, cider and pre-mixed drink and glasses of wine all contain more than 1 standard drink. Ditto for cocktails which contain more than one shot of spirits or liqueur. Bottom line: the calories add up.

Nutrients in alcoholic beverages

Besides alcohol, many alcoholic drinks contain carbohydrate (mainly sugar). Some might contain some fat and/or protein (which also contribute to total kilojoules) and/or caffeine.

Comparing alcoholic drinks is tricky due to the wide variability in serving sizes and alcoholic percentage. Below are a couple of charts comparing different drinks per 100g, using data from the AUSNUT database (1).

The chart below has the volume adjusted to typical serving sizes: 375ml for beer, ciders and mixed drinks, 250ml for cocktails, 150ml for wine, 50ml for fortified drinks and liqueurs, 30ml for spirits.

Standard drinks

In Australia, alcoholic beverage labels must include the number of standard drinks. The same applies for imported beverages. If you come across a bottle that does not have this on the label, you can calculate it with this formula:

# standard drinks = volume (ml) * % alcohol * 0.789

Example: # standard drinks in a 375ml can of beer that has 4.8% alcohol = 0.375 * 4.8 * 0.789 = 1.4 standard drinks

Alcohol and health

You’ve probably heard that drinking a glass or two of wine a day is good for you. However, alcohol consumption has also been link to detrimental effects on health. The Australian Dietary Guidelines (2) are informed by a large body of evidence. Below is a summary of the potential effects of drinking.

Positive

  • Moderate consumption of alcohol (1 standard drink for women, 1.5 to 2 for men) may reduce risk of cardiovascular disease, increase HDL cholesterol and have a mild anti-coagulant effect.
  • Some alcoholic beverages, such as wine, contain bioactive flavonoids, which may be beneficial for health.

Negative

  • Consumption of alcohol is associated with increased risk of breast and oesophageal cancer.
  • Heavy drinking can affect the structure of the brain in young adults, leading to cognitive impairment.
  • Alcoholics can develop Wernicke-Korsakoff syndrome due to thiamine deficiency. Symptoms include: disturbances in gait, paralysis of eye muscles and irreversible memory loss.
  • Alcohol can raise blood pressure and increase the risk of arrhythmias, shortness of breath, some types of cardiac failure, haemorrhagic stroke and other circulatory problems.
  • Alcohol interferes with glucose metabolism due to its effect on insulin and glucagon. This is particularly important for people with diabetes.
  • Alcohol consumption can be associated with the consumption of junk food, energy drinks, added sugars, etc.

Having said that, drinking alcoholic beverages might confer health benefits that go beyond the physiological effects of their components. For example, for some people having a few drinks with loved ones might decrease stress and strengthen community bonds.

Guidelines

The current guidelines from the National Health and Medical Research Council are as follows (3):

“Guideline 1: Reducing the risk of alcohol-related harm over a lifetime

The lifetime risk of harm from drinking alcohol increases with the amount consumed.

For healthy men and women, drinking no more than two standard drinks on any day reduces the lifetime risk of harm from alcohol-related disease or injury.

Guideline 2: Reducing the risk of injury on a single occasion of drinking

On a single occasion of drinking, the risk of alcohol-related injury increases with the amount consumed.

For healthy men and women, drinking no more than four standard drinks on a single occasion reduces the risk of alcohol-related injury arising from that occasion.

Guideline 3: Children and young people under 18 years of age

For children and young people under 18 years of age, not drinking alcohol is the safest option.

A. Parents and carers should be advised that children under 15 years of age are at the greatest risk of harm from drinking and that for this age group, not drinking alcohol is especially important.
B. For young people aged 15−17 years, the safest option is to delay the initiation of drinking for as long as possible.

Guideline 4: Pregnancy and breastfeeding

Maternal alcohol consumption can harm the developing fetus or breastfeeding baby.

A. For women who are pregnant or planning a pregnancy, not drinking is the safest option.
B. For women who are breastfeeding, not drinking is the safest option.”

Recommendations

In addition from following the guidelines above, consider the following recommendations:

  • If you have problems controlling your alcohol intake or have health conditions that are affected by alcohol (e.g. liver issues, alcohol metabolism deficiencies, severe gout), it would be better for you to don’t drink at all.
  • If you don’t want to drink but feel social pressure, order sparkling water with ice and lime or lemon.
  • If you choose to drink:
    • If alcohol triggers you to eat junk food, drink less frequently. Note that this doesn’t give you permission to binge drink. Also, don’t keep junk food in your house.
    • Drink at least one glass of water for every alcoholic beverage.
    • Avoid beverages that have added sugar or caffeine.
    • Don’t drink something if it doesn’t agree with you. For example, if you have histamine intolerance, you might want to avoid wine and beer. If tequila gives you headaches, stay away from it.
    • If you have blood glucose control issues or are following a low carbohydrate diet, your best options are spirits (on the rocks or mixed with sparkling water), red wine and dry white/sparkling wine.
    • If you have Coealiac Disease or gluten intolerance and want to drink beer, there are a couple of gluten-free alternatives available in major bottle shops and some pubs: O’Brien and Wilde. Cider is also gluten-free but much higher in sugar.
    • Avoid drinking right before going to bed because alcohol interferes with sleep quality.

More information and useful calculators can be found at drinkwise.org.au.

References

  1. Food Standards Australia New Zealand. AUSNUT 2011–13 – Australian Food Composition Database. 2014 [Available from: www.foodstandards.gov.au].
  2. National Health and Medical Research Council. Australian Dietary Guidelines. Canberra: National Health and Medical Research Council; 2013.
  3. National Health and Medical Research Council. Australian guidelines to reduce health risks from drinking alcohol. Canberra: Commonwealth of Australia; 2009.
  4. Australian Bureau of Statistics. 43640DO004_20112012 Australian Health Survey: Nutrition First Results – Foods and Nutrients, 2011–12 – Australia. 2014.

[Photo by Moss on Unsplash]

health benefits of nuts

Health benefits of nuts

The health benefits of nuts are widely accepted in many cultures. Most traditional cuisines incorporate nuts in one way or another. Nuts are part of many dietary patterns, including vegan (raw or regular), vegetarian, pescetarian, paleo, keto, Mediterranean, etc.

Tree nuts and peanuts

Tree nuts include walnuts, almonds, macadamia nuts, etc. Peanuts are botanically legumes, but are considered in the “nut” category due to its similar nutritional profile. Sadly, they also share the potential to cause food allergy. Both tree nuts and peanuts are in the list of top ten food allergens that must be declared in food packaging (read more about food allergy here).

Most scientific studies include peanuts when analysing nut consumption. Likewise, the Australian Dietary Guidelines consider peanuts in the nut category.

Nutrients in nuts

Nuts are energy-dense due to their high fat content. Depending on the type of nut, they also provide some protein and fibre. This make them ideal for controlling hunger. See table below for average values per 100g of raw nuts (1).

Different nuts have different proportions of the main kinds of fatty acids: saturated (SFA), monounsaturated (MUFA) and polyunsaturated (PUFA). See table below for average content per 100g of nuts (1). MUFAs and PUFAs are less stable than SFAs, hence the proclivity of nuts to become rancid. The human body requires a mixture of fatty acids, and, in general, it is better to obtain them from whole foods such as nuts.

Nuts also contain micronutrients such as polyphenols, which also confer health benefits.

Diabetes

The analysis of a large cohort study found that people who consumed walnuts had lower relative risk of diabetes compared to people who didn’t consume nuts at all (2).

Almonds, pistachios and peanuts may help control blood sugar and insulin (3).

Body composition

The UK Women’s Cohort Study found that higher nut consumption was associated with lower body weight, body mass index (BMI) and waist circumference. The researchers also analysed the results grouped by food preferences. Some of the benefits seemed to be more pronounced for omnivores than vegetarians and vegans (4).

Almonds and peanuts increase satiety, allowing for better intake control. In addition, peanuts may help improve fat oxidation (3).

Cardiovascular risk

The same study also found higher nut consumption was also associated reduced blood pressure and blood cholesterol. Participants who ate more nuts also had less prevalence of heart attack, diabetes and gallstones (4).

Walnuts in particular have been linked to improvements in blood lipids and endothelial function (3, 5). The phytosterols, unsaturated fatty acids and fibre in nuts seem play a role in the former, and alpha-linolenic acid (ALA), a PUFA that contributes 10% of the energy in walnuts, may be responsible for the latter (5).

Pistachios have also been associated with favourable changes in blood lipids and vascular function (3).

Nuts also contain potassium, which seems to counteract the effects of excess sodium on elevating blood pressure (5).

Inflammation and oxidative stress

An analysis of 2 large cohort studies found that higher nut consumption was associated with lower concentrations of the following inflammatory markers: C-reactive protein (CRP) and interleukin-60 (IL-6), but not tumor necrosis factor receptor 2 (TNFR2). This association also was noted when 3 servings of nuts replaced the same number of servings of red meat, processed meat, eggs or refined grains. The same relationship was found for CRP when nuts replaced potatoes and potato chips (6).

Walnuts contain g-tocopherol, a potent antioxidant that aids in reducing inflammation (3, 5). A type of polyphenol in walnuts, called ellagitannins, have also been linked to antioxidant and antiinflammatory activities (5).

Brazil nuts are rich in selenium, which has antioxidant properties (3).

Recommendations

  • If you have a nut allergy, make sure you let people know in restaurants, airplanes, functions, etc. It’s better to be safe than sorry.
  • As a general rule, a reasonable intake of nuts is around 30g per day. This may be adjusted based on age, gender, body mass, activity level, etc.
  • Raw, dry roasted and “activated” (soaked, then dried) nuts are best
  • When possible, keep nuts in the freezer or fridge to protect the fatty acids
  • Don’t eat nuts that taste or smell rancid
  • Eat a variety of nuts to ensure a wide exposure to beneficial nutrients
  • If you don’t like to eat nuts on their own, try adding them to salads, yoghurt, etc.
  • If you struggle with portion control and/or want to lose weight, the following strategies can be useful:
    • Buy single-serve packages or use small containers to portion your daily snack
    • Buy nuts in the shell and shell them before eating
    • Choose whole nuts instead of nut butters
    • Avoid making treats with nut meal or butter

References

  1. Food Standards Australia New Zealand. AUSNUT 2011–13 – Australian Food Composition Database. 2014 [Available from: www.foodstandards.gov.au].
  2. Arab L, Dhaliwal SK, Martin CJ, Larios AD, Jackson NJ, Elashoff D. Association between walnut consumption and diabetes risk in NHANES. Diabetes/metabolism research and reviews. 2018;34(7):e3031.
  3. de Souza RGM, Schincaglia RM, Pimentel GD, Mota JF. Nuts and Human Health Outcomes: A Systematic Review. Nutrients. 2017;9(12).
  4. Brown RC, Gray AR, Tey SL, Chisholm A, Burley V, Greenwood DC, et al. Associations between Nut Consumption and Health Vary between Omnivores, Vegetarians, and Vegans. Nutrients. 2017;9(11):1219.
  5. Ros E, Izquierdo-Pulido M, Sala-Vila A. Beneficial effects of walnut consumption on human health: role of micronutrients. Current opinion in clinical nutrition and metabolic care. 2018;21(6):498-504.
  6. Yu Z, Malik VS, Keum N, Hu FB, Giovannucci EL, Stampfer MJ, et al. Associations between nut consumption and inflammatory biomarkers. The American Journal of Clinical Nutrition. 2016;104(3):722-8.

[Photo by Tom Hermans on Unsplash]

lucuma

What is lucuma (and how to pronounce it)

Lucuma (written lúcuma in Spanish) is an Andean fruit that grows in Peru, Ecuador and Chile. It has been around since before the Incas and it’s still widely consumed in the region. Listen to the correct pronunciation in this link.

Lucuma is generally the size of an orange or grapefruit, although there are also smaller ones. The fruit has a thin green skin that splits open when ripe. The flesh is yellow-orange, sweet, firm and starchy. It has a few round medium-sized brown seeds.

lucuma

Culinary uses

In Peru, the fruit can be found fresh (mainly during summer months), frozen and powdered (also known as “harina de lúcuma). The availability of the powder seems to have diminished with time, perhaps due to exports.

Lucuma is normally not eaten by itself, but mostly used in smoothies and desserts. It pairs well with dairy and chocolate. It is also used in cocktails and confectionery.

Below are a couple of recipes using the powdered version:

Nutrients in lucuma

Fresh lucuma is high in carbohydrate and contains some fibre and vitamins. Below is a comparison between the fresh and powdered versions (1).

How does fresh lucuma compare to apples, bananas and oranges (i.e. the most commonly eaten fruits in Australia)? It has more carbohydrate, less fibre and less vitamin C per 100 grams, as shown in the table below (1, 2).

Of course, if you live in Australia you will most likely come across the powder and not the fresh fruit. See table below for a comparison to other powders that are somewhat common ingredients in things like smoothies: cacao, beetroot and acai powder (1, 3).

Lucuma also contains a high amount of phenolic compounds compared to other Peruvian fruits (4).

Health benefits

The phenolics in lucuma have antioxidant activity. It may also help manage type 2 diabetes due to its inhibitory activity on the enzyme alpha-glucosidase (4).

There is also preliminary research suggesting that the specific fatty acids in lucuma seed oil may improve skin wounds and skin inflammatory conditions (5).

Superfood?

As other exotic fruits, lucuma has received a bit of attention lately. Many brands in Australia offer lucuma powder and I’ve seen it offered as an ingredient for smoothies in Sydney. There is also a brand of popcorn that has lucuma powder among other “superfoods” although they have spelled it wrong in their website and packaging. I have seen this misspelling elsewhere in the web as well. See screenshots below.

References

  1. Fundación Universitaria Iberoamericana. Base de Datos Internacional de Composición de Alimentos. 2017 [Available from: https://www.composicionnutricional.com/alimentos].
  2. Food Standards Australia New Zealand. AUSNUT 2011–13 – Australian Food Composition Database. 2014 [Available from: www.foodstandards.gov.au].
  3. US Department of Agriculture, Agricultural Research Service, Nutrient Data Laboratory. USDA National Nutrient Database for Standard Reference, Release 28. Version Current: September 2015 [Available from: https://ndb.nal.usda.gov/ndb/].
  4. Pinto Mda S, Ranilla LG, Apostolidis E, Lajolo FM, Genovese MI, Shetty K. Evaluation of antihyperglycemia and antihypertension potential of native Peruvian fruits using in vitro models. Journal of medicinal food. 2009;12(2):278-91.
  5. Rojo LE, Villano CM, Joseph G, Schmidt B, Shulaev V, Shuman JL, et al. Wound-healing properties of nut oil from Pouteria lucuma. J Cosmet Dermatol. 2010;9(3):185-95.
caffeine and performance

Caffeine and performance

Caffeine is a known ergogenic (i.e. performance-enhancing) substance used by many athletes participating in various disciplines. But does it work for all types of exercise? What are the mechanisms behind caffeine and performance? How does it impact health?

Caffeine as a supplement

Caffeine is an alkaloid present in plants such as coffee that acts as an stimulant. The form commonly used as a sports supplement is called anhydrous caffeine and comes in various presentations, including pills, powders, gums, gels and liquids. It can also be consumed in the form of coffee or tea, although this makes it difficult to figure the exact amount of the active compound.

Endurance sports

Researchers have consistently found a positive relationship between caffeine and performance in endurance sports. The generally recommended dose is 3-6 mg caffeine/kg bodyweight taken 60 minutes before exercise (1, 2). In addition, athletes may also utilise lower doses taken before and during the event (2).

Strength and power

A systematic review including 10 studies assessing the effect of caffeine and performance in strength and power exercises. The number of participants per study was small and the majority of subjects were male. The researchers found that caffeine improved upper body (but not lower body) strength and muscle power as measured by vertical jumps (3).

A study with 54 trained young men examined the effect of 300 mg of caffeine anhydrous, the equivalent dose from coffee or placebo on strength exercises. They were tested on one-rep max and repetitions to fatigue of leg press and bench press. There was no difference between the groups (1). The same study also tested participants on a bike sprint test. Average total work was higher for participants who consumed caffeine in either form (1).

Mechanisms behind caffeine and performance

Caffeine’s ergogenic effects might be exerted by effects on adenosine receptors in which it acts as an antagonist, reduced pain/effort perception (1, 2, 3), release of endorphins, increased alertness (2) and improvements in neuromuscular function – including motor unit recruitment (2, 3).

caffeine chemical structure

Chemical structure of caffeine (3)

Health effects

Excessive consumption of caffeine can produce negative side effects, such as nausea, anxiousness and insomnia. This may happen with doses equal or higher to 9 mg/kg bodyweight. In addition, these doses do not seem to provide extra performance benefits (2).

It is also thought that caffeine produces excessive diuresis (urine production), subsequently causing dehydration. A meta-analysis of 16 studies involving 379 participants found that caffeine intake does not produce excess diuresis to the level that could be detrimental to an athlete. This could only be a problem in multi-day events (5).

Finally, it’s important to note that a great amount of caffeinated pre-workout supplements also contain other substances, some of them banned, that could negatively impact health. When in doubt, consult with a sports dietitian, particularly if you compete on regulated sports. If you are not an elite/professional athlete, you can try consuming coffee or tea instead. You can find more about the nutrition and health effects of coffee in this post).

References

  1. Trexler ET, Smith-Ryan AE, Roelofs EJ, Hirsch KR, Mock MG. Effects of coffee and caffeine anhydrous on strength and sprint performance. European journal of sport science. 2016;16(6):702-10.
  2. Peeling P, Binnie MJ, Goods PSR, Sim M, Burke LM. Evidence-Based Supplements for the Enhancement of Athletic Performance. International Journal of Sport Nutrition and Exercise Metabolism. 2018;28(2):178-87.
  3. Grgic J, Trexler ET, Lazinica B, Pedisic Z. Effects of caffeine intake on muscle strength and power: a systematic review and meta-analysis. Journal of the International Society of Sports Nutrition. 2018;15:11.
  4. National Center for Biotechnology Information. PubChem Compound Database; CID=2519, https://pubchem.ncbi.nlm.nih.gov/compound/2519 (accessed Oct. 12, 2018).
  5. Zhang Y, Coca A, Casa DH, Antonio J, Green JM, Bishop PA. Caffeine and diuresis during rest and exercise: A meta-analysis. J Sci Med Sport. 2015 September; 18(5): 569–574.

[Photo by Afrah on Unsplash]

food allergy

Food allergy, intolerance and preference

Do you know what is the difference between a food allergy, a food intolerance and a food preference? Why would you care? Well, if you work in an industry that involves serving or selling food to people (food manufacturer, restaurant, cafe, pub, bar, hospital, aged care facility, school, airline, catering company, hotel, bed & breakfast, food truck, etc.), you should.

Food Allergy

Allergy is an immune reaction to substances (allergens), which are usually harmless. The immune system reacts by producing antibodies.

The most common triggers are proteins in the following foods:

  • Peanut
  • Tree nuts
  • Milk
  • Eggs
  • Sesame
  • Fish
  • Shellfish
  • Soy
  • Wheat
  • Lupin

Allergic reactions can include hives, swelling of lips/eyes/face, abdominal pain, vomiting, wheeze. Reactions in infants include: colic, reflux, eczema, chronic diarrhoea and failure to thrive.

The most severe reaction is anaphylaxis, which can lead to death (although it’s not common in Australia and New Zealand). Anaphylaxis can be prevented by immediate administration of adrenaline (e.g. Epipen).

The current prevalence of food allergy is (1):

  • 10% of children up to 1 year old
  • 4-8% of children up to 5 years
  • 2% adults

Food allergies are on the rise and there are several hypotheses of why this is the case. However, the jury is still out.

Most food allergies in children are not severe and can be outgrown. Allergies to peanuts, tree nuts, seeds and shellfish are less likely to be outgrown.

Food allergies can be diagnosed by skin prick test or blood test and/or temporary elimination diet with food/capsule challenges under medical supervision.

Unproven and inappropriate methods that claim to test for allergy or intolerance include IgG testing to foods, cytotoxic food testing, kinesiology, Vega testing, electrodermal testing, pulse testing, reflexology and hair analysis.

Coeliac Disease

Coeliac Disease (CD) is not an allergy, but a condition that involves an immune response (hypersensitivity) to gluten, a protein present in wheat, rye, barley and oats. In people with CD, ingestion of gluten causes damage to the small intestine.

CD can begin at any age. Symptoms include but are not limited to: nutrient malabsorption, diarrhoea, abdominal cramps, bloating, nausea and vomiting. Non-digestive symptoms can include dermatitis, mouth ulcers, depression, brain fog, headaches, infertility, etc.

The estimated prevalence of CD in Australia is 1 in 70 people, with 4 out of 5 remaining undiagnosed (2).

Diagnosis is made using the following steps:

  1. Blood screening to assess antibodies and/or genetic markers
  2. Small bowel biopsy to confirm damage. Note that this has to be done after a period of gluten consumption. If your doctor tries to test you for CD even though you have told them you are not eating gluten, run the other way.
  3. Repeat biopsy after a gluten-free period to confirm recovery

The only treatment for CD is management through a gluten-free diet.

Food intolerance

Food intolerance does not involve the immune system, but it’s caused by the irritation of nerve endings.

The trigger is a build-up of natural or artificial chemicals in food, such as:

  • Glutamates (MSG, Camembert cheese, Parmesan cheese, tomatoes, soy sauce, mushrooms)
  • Amines (pineapples, bananas, baked meat, vegetables, red wine, wood-matured white wine, avocados, chocolate, citrus fruits, mature cheese)
  • Salicylates (herbs, spices, fruits, vegetables, aspirin)
  • Additives (natural and artificial colours, sulphites)

The most common symptoms are: hives, swelling, stomach & bowel irritation, headaches, tiredness and behaviour changes (moodiness, irritability, restlessness). Intolerance to food does not typically cause severe allergic reactions such as anaphylaxis.

Because food intolerance does not show on allergy testing, diagnosis is made by temporary elimination diet with subsequent food or capsule challenges. As with food allergy, unorthodox tests can be misleading (3).

Management is done through dietary modification; i.e. including foods with problematic chemicals below each person’s tolerance threshold.

Prevalence of food intolerance is not known but statistics of food avoidance can give a hint. The graph below shows the proportion of people who reported avoiding particular foods due to allergy or intolerance in the Australian Health Survey 2011-12 (4).

Food preferences

These are avoidance of certain food or food groups for a wide array of reasons, from taste to religion. Diets that cater to food preferences include: vegan, vegetarian, pescetarian, kosher, halal, paleo, keto, low-carb, etc. Note that there can be an overlap between food preferences and intolerances (or even allergies), for example one can choose to follow a paleo diet because they are intolerant to gluten and dairy.

The following graphs show a comparison of people who reported avoiding foods due to allergy/intolerance vs cultural, religious or ethical reasons (4).

The graph below shows the foods avoided for cultural, religious or ethical reasons (4).

What to do

The degree of avoidance of certain foods will depend on the type and severity of the adverse reaction. People with food allergies or Coealiac Disease typically need to be more vigilant than people with food intolerance.

Below are a few tips that might make life easier when food preparation is out of your control:

  • Read labels. The major allergens must be declared in all packaged foods.
  • Check menus before eating out and ask the restaurant if the menu is not descriptive enough.
  • Indicate dietary requirements when registering for work functions, conferences, etc.
  • Most airlines and even interstate trains offer special meals. If you’re not sure or your airfare does not include a meal, bring food that is safe for you or fast.
  • Bring backup snacks to parties, picnics, etc.
  • Be honest. There are people who suggest claiming allergies so that restaurants, hospitals, etc. are willing to cater to what is not a health-threatening intolerance or preference. In my opinion, it is better to be upfront and clear with your requests. This also can prevent businesses from dismissing actual allergies just because “everyone claims to have an allergy”.

Further to the above, if you are avoiding particular foods or food groups, please make sure you are meeting your nutritional needs. Also, remember some adverse reactions might be exacerbated by underlying issues (e.g. gut health) and some might change over time. Work with a dietitian in case you need help.

References

  1. Australasian Society of Clinical Immunology and Allergy. Food Allergy [Available from: https://www.allergy.org.au/patients/food-allergy/food-allergy].
  2. Coeliac Australia. Coeliac Disease [Available from: https://www.coeliac.org.au/coeliac-disease/.
  3. Australasian Society of Clinical Immunology and Allergy. Food Intolerance [Available from: https://www.allergy.org.au/patients/food-other-adverse-reactions/food-intolerance].
  4. Australian Bureau of Statistics 2004, Australian Health Survey: Nutrition First Results – Foods and Nutrients, 2011-12, ‘Table 14: Food avoidance due to allergies or intolerances then type of food avoidance for cultural, religious or ethical reasons’, data cube: Excel spreadsheet, cat. no. 6261.0.55.00, viewed 30 September 2018

[Photo by Tom Hermans on Unsplash]

Healthy Gut Healthy You

Book review: Healthy Gut Healthy You (Dr Michael Ruscio)

Healthy Gut Healthy You is the long-awaited book by Dr Michael Ruscio, an American functional medicine practitioner, researcher and podcaster. Dr Ruscio started off as a chiropractor and discovered functional medicine during his own healing journey. He focuses on treating the gut as the first step for improving a wide range health conditions, many of which don’t manifest as gastrointestinal discomfort.

In both his book and his podcast, Dr Ruscio offers a very sensible clinical approach. I think this is a product of working with real patients and noting what actually works. He avoids dogma and excessive testing, restrictions and treatment.

Healthy Gut Healthy You

The book has 5 parts: The Importance of Your Gut, Diet for Optimum Gut Health, Lifestyle and Environments for Optimum Gut Health, Tools for Healing Your Gut and The Great-in-8 Action Plan. It is written in a simple language for the non-scientific reader to understand. Each chapter of the book is followed by several pages of scientific references for those interested in cross-checking the sources. I think it’s a valuable resource for clinicians and people facing health issues. Having said that, there are parts of the protocol that are best implemented with the help of a clinician.

Gut basics

Part 1 sets up the stage for the rest of the book. It briefly describes the anatomy and function of the small and large intestine. Then it explains how derangement in the gut, such as bacterial overgrowth, can cause a wide array of health issues.

Another important topic covered in this section of the book is how to determine which scientific papers are worth considering. With the amount of scientific papers being published these days and the bad job that journalists do at communicating science, it is important to sharpen critical skills.

This part also covers the impact of early life bacterial exposure on health.

The importance of diet

The second section of the book deals with diet and its effects on our health and the health of our gut bacteria. Dr Ruscio emphasises the importance of focusing on reducing inflammation and balancing blood sugar first in order to create a healthy environment. Only then we can worry about feeding our gut bacteria (i.e. prebiotics).

This part of the book also covers Coeliac Disease and non-Coeliac gluten sensitivity. Other topics include appropriate amounts of carbohydrate for each individual and the issue with processed foods.

Fibre is another interesting topic in this section, as more is not always better. This is particularly the case for gut-related conditions such as irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD).

Beyond food

Part 3 of the book highlights the importance of the environment and lifestyle on gut health. This includes topics such as vitamin D, sun exposure, time in nature, sleep and stress management.

Supplements, etc.

The next section of the book explores other treatments that can help with particular health conditions, including probiotics, digestive enzymes, etc.

Dr Ruscio has a very practical way of looking at probiotics. Rather than focusing on brands he divides probiotics into 3 categories depending on which types of microorganisms are present in them. This is based on the observation that a particular category might work better than others for a particular condition and/or for particular people. Using this approach, one can save time and money by trying different categories of probiotics rather than a many different brands within the same category.

This section also covers antibacterial treatments that can be used to remove parasites, for example, and the use of liquid supplements designed to provide complete nutrition while allowing the gut to heal.

Other topics in this section are prokinetics (which stimulate intestinal motility), fibre supplements, prebiotics and fecal transplants.

The plan

The final part of the book details Dr Ruscio’s protocol named The Great-in-8 Action Plan. As its name implies, it contains 8 steps but not everyone needs to follow all of them. Some people might experience significant improvement with just changing their diet, for example.

The protocol includes, as most sensible protocols, the elimination of suspect foods with later reintroduction of non-problematic foods. A note for the anti-paleo crowd: Dr Ruscio does recommend a paleo diet (either standard or the autoimmune version) or a low-FODMAP diet for the elimination step. I agree that eliminating grains, legumes and dairy can be an effective way of pressing the reset button. I like the fact that Dr Ruscio puts particular emphasis on the reintroduction step with the aim of eating the wider variety of foods possible.

More info

Head to Dr Ruscio’s website for more information about his book and his work. Also check out his podcast Dr Ruscio Radio.

coffee

What’s in your coffee shop beverage?

Australians love their coffee, although not as much as several Nordic and European countries (we didn’t make the list of top 20 coffee drinking countries in 2017). Australia is also a big consumer of tea, ranking #13 according to the same source. From the results of the latest Australian Health Survey (2011-12), 53.6% of women and 38.9% of men 19+ years old drink tea; 57.5% of women and 57.0% of men (19+ years old) drink coffee or coffee substitutes (1). If you fall in these groups, do you know what’s in your coffee shop beverage?

Caffeine

The main reason people drink coffee is caffeine, a stimulant found in coffee, tea, chocolate, etc. Caffeine affects people in different ways, mainly due to the individual metabolism variability.

Current recommended caffeine intake is less than 600 mg per day for the general adult population and less than 200 mg per day if you are stressed or pregnant (2).

The following graphs are based on data from the Australian Health Survey 2011-12 (1). See graph below for average caffeine content in coffee shop drinks (assuming an average regular coffee is 250ml, an average espresso is 30ml and an average macchiato is 40ml).

Fluid

Coffee and tea are liquids, and as such, do count toward your daily consumption of fluid. Some people think they shouldn’t because they “are diuretic” but under normal circumstances, the net contribution of these beverages is positive fluid.

Milk

According to The 2017 Square Australian Coffee Report, these are the most popular beverages ordered at cafes:

  • Latte (39%)
  • Flat white (24%)
  • Cappuccino (16%)
  • Long black (8%)
  • Hot chocolate (4%)
  • Mocha (4%)
  • Iced drinks (3%)
  • Chai (2%)

Below is the flat white vs latte consumption per state from the same source:

Energy

Note that the vast majority of beverages sold at coffee shops are milk-based. Milk is a nutritious food, but, as mentioned above, it can make a huge difference in energy intake, particularly if you drink full-fat milk. Every gram of fat contributes 37.7 kilojoules (~9 Calories).

See graph below for average energy content and energy from fat in coffee shop drinks. Note that energy will vary with size, type of milk, added sugar and added syrups/toppings.

Carbohydrates

Milk also contains carbohydrates, which contribute 16.7 kilojoules (~4 Calories) per gram. Most of the carbohydrates in unsweetened milk-based beverages come from sugars such as lactose in the case of cow’s milk and anything from plain cane sugar to maltodextrin in the case of non-dairy milks.

See graph below for average carbohydrate (in grams) and sugar (in teaspoons) in coffees/teas. Note that these figures do not include any added sugars.

Protein

The protein in milk-based beverages comes from whey and casein in the case of cow’s milk, soy protein in the case of soy milk, etc. Protein contributes 16.7 kilojoules (~4 Calories) per gram. If you are either looking to limit or increase protein, be mindful of your beverage choice (black vs milk-based) or milk choice (you can always order half, 3/4 or extra milk in most cafes if need be).

Calcium

Cow’s milk and enriched soy milk contain calcium, which is important for bone health, neuromuscular and cardiac function, blood clotting and hormone release. Note that the calcium content in other non-dairy milks, such as almond milk, is likely to be significantly lower.

See graph below for average protein and calcium content (in general, directly proportional) in coffee shop drinks. Note that I’ve only included drinks made with full-fat and skim cow’s milk and regular soy milk.

Coffee and health

A 2017 umbrella review of studies summarised coffee effects on all cause mortality, cardiovascular disease, cancer, metabolic disease, as well as liver, gastrointestinal, renal, musculoskeletal, neurological, gynaecological and antenatal outcomes. The authors concluded “Overall, there is no consistent evidence of harmful associations between coffee consumption and health outcomes, except for those related to pregnancy and for risk of fracture in women” (3).

References

  1. Australian Bureau of Statistics. 43640DO004_20112012 Australian Health Survey: Nutrition First Results – Foods and Nutrients, 2011–12 – Australia. 2014.
  2. Centre for Population Health. Caffeine 2013 [updated 11 July 2013. Available from: https://www.health.nsw.gov.au/aod/resources/Pages/caffeine.aspx.
  3. Poole R, Kennedy OJ, Roderick P, Fallowfield JA, Hayes PC, Parkes J. Coffee consumption and health: umbrella review of meta-analyses of multiple health outcomes. BMJ. 2017;359.
SunRice rice cups

Product review: SunRice rice cups

SunRice rice cups are made by one of the main brands rice available in Australia. Back in the day rice used to be just rice, and people would have whatever rice was common in their place of origin. For example, medium grain rice is the norm in Perú, and we use it for most things – savoury and sweet. Brown rice became popular as people got more interested in health and other types of rice started appearing on shelves as consumers got interested in trying other cuisines (e.g. basmati for Indian curries, glutinous rice for sushi, arborio for risotto, bomba for paella).

Similarly, a greater interest in consuming other grains considered highly nutritious, has created a market for blends of grains which can be used as a substitute for plain rice. In parallel, the convenience factor has driven a market of microwaveable foods which, as you will see, doesn’t necessarily mean hyper-processed unhealthy junk.

The cups

SunRice cups contain blends of rice and other grains that have been precooked and are ready to be reheated. I got the following samples at a conference:

  • SunRice Super Grains Gluten Free Tri Blend Cup with brown rice, red rice and quinoa
  • SunRice Super Grains Gluten Free Super Duo Cup with brown rice and riceberry rice
  • SunRice Super Grains Gluten Free Multigrain Blend Cup with brown rice, red rice, buckwheat, quinoa and chia

Pros

  • Convenience
  • Good portion size, particularly for people who have problems regulating their servings
  • Higher in protein and fibre than plain rice
  • More interesting flavour and texture than plain rice
  • All cups are gluten-free

Cons

  • Plastic. No matter what the manufacturer says, I don’t like to heat plastic in the microwave. Also more packaging that goes to landfill.
  • It can be too big of a portion size for people who need to regulate their carb intake, and the cup can’t be re-sealed when opened. If that’s the case, you might be better off eating cauliflower rice or mixing a small amount of rice with lupin flakes instead.
  • Higher in protein and fibre than plain rice
  • Apart from the cooked grains, the cups contain sunflower oil and stabiliser (471), presumably to improve the texture of the final product, but I find it gives the rice a chalky mouthfeel. Also, some people with food chemical intolerance can be sensitive to the stabiliser.

Nutrition

See the panels below for 2 of the SunRice rice cups that I tried:

Super Duo:

Nutrition Facts
Serving Size 125g
Servings Per Container 2

Amount Per Serving
Calories 214 Calories from Fat 38.7
% Daily Value*
Total Fat 4.3g 7%
Saturated Fat 1.0g 5%
Trans Fat g
Cholesterol mg 0%
Sodium 18mg 1%
Total Carbohydrate 39.9g 13%
Dietary Fiber 2.6g 10%
Sugars 0.9g
Protein 4.1g 8%

*Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.

Multigrain Blend:

Nutrition Facts
Serving Size 125g
Servings Per Container 2

Amount Per Serving
Calories 220 Calories from Fat 35.1
% Daily Value*
Total Fat 3.9g 6%
Saturated Fat 0.8g 4%
Trans Fat g
Cholesterol mg 0%
Sodium 16mg 1%
Total Carbohydrate 41.5g 14%
Dietary Fiber 3.1g 12%
Sugars 0.9g
Protein 4.8g 10%

*Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.

The verdict

I think SunRice rice cups are good to have in hand if you absolutely have zero time to cook. If you are somewhat organised and have some spare minutes, you can batch-cook your own blend of grains, portion them up and freeze for later.

More info

Head to SunRice’s website to learn more about their steamed rice (and other) products:

food photos

Food photos: the good, the bad, the ugly

No, this is not an article about good/bad/ugly photos on social media. Rather, it’s a brief analysis of potential pros and cons of what’s happening with food photos in social media.

My food photography story

I was born in the pre-digital camera era. My first camera was a black and white film Kodak. I was 8 or 9 and would take photos of me and my sisters, the dog, etc. Back then, it didn’t even occur to me about taking pictures of meals, even though I’ve always loved food. In retrospect, that’s a good thing, considering what I used to eat until well into my 20s.

My first blog, which started in Feb 2006, was in Spanish and had a decent amount of articles about food. However, there were not many photos; taking pictures of your meals was not a thing yet, at least not in Perú. See screenshot below of a post about coriander in which I mention 15 different dishes and a restaurant without a single photo. Even when I started my food blog Lateral Eating in 2009, taking photos of food in public was not always socially acceptable.

And then Instagram happened. Soon after its launch in October 2010, more and more people started taking and posting pictures of their food. In the beginning, some (most?) restaurant owner/managers were not very keen on people taking photos of their meals. Some claimed it was annoying to other diners, but I think it was more of a fear of exposing the actual plated meals to public scrutiny.

For a percentage of the population, Instagram is just an instrument of procrastination. Yes, they look at food pictures which might make them hungry or crave a burger, but they don’t engage at a deeper level with the images. Likewise if they are the ones posting the photos: they snap it, don’t filter it, post it and forget about it. The rest of Instagram users might experiment some sort of effect, either positive or negative, after posting or seeing food photos.

Food photos – the good

As a dietitian, I take diet histories all the time. Some people are pretty good at remembering what they ate, some people need a bit of help, some people just lie. I once saw a young Asian guy in hospital who had a procedure earlier that day and couldn’t remember his meals. FOrtunately, he had snapped a photo of his tray, so writing down his diet history was a piece of cake. Similarly, there are a number of diet tracking apps that allow you to attach photos of your meals to your logs so that your dietitian can see what you actually ate. This is super useful.

A small study (convenience sample of 16 females) summarised all the things that are great about posting food photos, specifically on Instagram (1):

  • You can keep track of your food intake and how it relates to your goals
  • You can connect socially with people who share the same interests
  • You can motivate other people to cook, eat healthy, etc.
  • You can share information, such as recipes
  • You can use it as an accountability tool for yourself and others

Food photos – the bad

Once you realise that posting a photo on social media means that it’s out there for the entire world to see, posting pictures of your meals can get stressful in a few different ways:

  • You might feel bad if you have not posted any photos in the last X amount of time
  • You might feel guilty if you haven’t had anything healthy to eat and therefore you decide not to post a photo of what you actually ate
  • You might feel disappointed because your food photos don’t look as good as someone else’s
  • You might annoy/embarrass your dining companions by taking photos of your meal in public
  • You might miss out on quality time with your loved ones because you were focusing on taking the perfect shot

Food photos – the ugly

A larger study (convenience sample of 680 females) explored the relationship between social media and othorexia nervosa, an unhealthy obsession with “clean eating”. The prevalence of this condition (note: it is not recognised as an official diagnosis yet) is estimated to be less than 1%. Participants answered a questionnaire about social media use and eating habits, to determine their tendency towards othorexia nervosa. The researchers found that this tendency was greater in people who had higher Instagram use. In addition, other studies have found associations between social media use and depression, negative social comparison and isolation (2).

Parting thoughts

Given the rapid growth of social media users (as an example, see chart below), it is concerning that the percentage of people who are negatively affected by food photography on will grow in a similar pattern.

Our best bet is to keep our eyes and ears peeled for potential signs of emotional distress and/or obsessive behaviours in ourselves and people around us.

References

  1. Chung CF et al. When Personal Tracking Becomes Social: Examining the Use of Instagram for Healthy Eating. Proc SIGCHI Conf Hum Factor Comput Syst. 2017 May 2; 2017: 1674–1687.
  2. Turner PG and Lefevre CE. Instagram use is linked to increased symptoms of orthorexia nervosa. Eat Weight Disord (2017) 22:277–284.