Nutrition
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Mineral overview
If you know minerals are micronutrients that are good for you but struggle to name more than 2 or 3, this mineral overview is for you. In this guide you will find the following information (when applicable or available) for the main minerals: Calcium Sources: dairy foods (e.g. milk, yoghurt, cheese) and in smaller amounts in fish with bones, legumes, dark green leafy vegetables (e.g. kale, spinach), certain nuts, fortified soy beverages and breakfast cereals. Bioavailability: absorption from milk is between 20 and 40%, from vegetables is either in the same range or lower, depending on the vegetable (higher in cruciferous vegetables). Absorption from food can be enhanced by fortification…
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Vitamin overview
If you know vitamins are micronutrients that are good for you but struggle to name more than 2 or 3, this vitamin overview is for you. In this guide you will find the following information (when applicable or available) for all vitamins: Vitamin A Forms: preformed and provitamin A carotenoids (e.g. β-carotene, α-carotene and β-cryptoxanthin), which can be converted to vitamin A. Solubility: fat-soluble. Sources: preformed vitamin A is found in animal foods and carotenoids are found in oils, green leafy vegetables (e.g. spinach and kale), carrots, fruits (e.g. mango, papaya, orange). The conversion factor of β-carotene to vitamin A depends on the source. Making 1 ug of vitamin A…
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What are micronutrients?
As a dietitian, I always advocate for variety in the diet to increase exposure to micronutrients. But what are micronutrients? Below is a quick overview, more in-depth articles to follow. As seen previously, macronutrients are the “bigger” components of food, namely protein, fat and carbohydrates. Water can be also considered a macronutrient, however it does not contribute any energy. Conversely, alcohol cannot be considered nutritious but does contribute energy. The prefix “macro” comes from the ancient Greek makrós, which means “long”. It is normally used to mean “big” or “large”. Thus, macronutrients are needed in large amounts in the diet (tens or hundreds of grams). The prefix “micro” comes from…
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How to adjust carbohydrate intake
How to adjust carbohydrate intake is the third article in this short series dedicated to this important source of fuel for physical activity. We have described what are carbohydrates and the use of carbohydrate for sports. In theory, carbohydrate requirements can be calculated knowing a few variables, however in practice there is often a mismatch between estimated and actual requirements. Sources of mismatch Wrong calculations Biological factors These include insulin sensitivity and glucose oxidation rates, which will determine how much carbohydrate the athlete can actually use for fuel. Health conditions Actual vs predicted output In many cases, this is the biggest source of mismatch. Some athletes can predict with a…
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Carbohydrate for sports
The use of carbohydrate for sports has been well-known for several decades. The amount and timing of carbohydrate intake depends on many factors, including the duration, intensity and type of exercise. Roles of carbohydrate in sport As seen in the previous article, the main role of carbohydrate in the body is the production of energy. During exercise, this can translate to: In the time between training or competition bouts, carbohydrate intake is important to: The amount of carbohydrate an athlete requires during and around exercise depends on several factors: It is important to mention the fact that the individual factors listed above can change with habits. When it comes to…
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What are carbohydrates?
Carbohydrates are a polarising subject. For some people, carbs are life, while others say they are the devil. In this article we explore what are carbohydrates, their roles, types and sources. What are carbohydrates? Carbohydrates, a.k.a. “carbs” are one of the macronutrients in our food. As the name “carbohydrate” implies, carbs contain carbon, hydrogen and oxygen, hence the sciency abbreviation “CHO”. The word “carbohydrates” is a noun often used to describe carbohydrate-containing foods. Many of these foods are staples in many traditional cuisines, for example rice, bread, pasta, noodles, potatoes, and taro. Roles of carbohydrates The main role of carbohydrate is energy production in the body. The amount of energy…
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Sodium in sports
At the population level, health authorities recommend limiting sodium intake to prevent chronic conditions. However, the role of sodium in sports is more complicated, as this electrolyte plays important roles related to performance and recovery. Roles of sodium As seen in the article How much salt is too much?, sodium has roles in the maintenance of plasma volume and transmission of nerve impulses. In addition, it is needed for muscle contraction and glucose transport into cells. As a reminder, glucose is essential for energy production during most types of exercise, as well as recovery post-exercise. Sodium in sports How do we lose sodium The main ways we lose sodium is…
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How much salt is too much?
If you have a heart condition, your doctor has probably told you to limit your salt intake. As it is impossible and undesirable to eliminate salt completely, it is important to know much salt is too much? Sodium vs salt Sodium is a mineral and what we know as salt (the one we use for seasoning our food) is sodium chloride. Therefore, the amount of salt we consume does not equal the amount of sodium we consume. Sodium in food manifests in other forms, not just as the salt that is added for seasoning. Sodium is involved in many processes in the body, including maintenance of plasma volume, acid-base balance,…
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Misreporting dietary intake
Misreporting dietary intake is more common than you think. This becomes an issue when we try to draw health, body composition and/or performance associations based on inaccurate data. The reasons for misreporting vary (not everyone lies on purpose) and does the level of misreporting (i.e. how far off are the reported vs “real” values). However, there are clear trends: for example, most people tend to underreport (say they ate less than they did) than overreport. What is misreporting dietary intake? Misreporting is failing to report with accuracy how much a person ate. Underreporting means reporting less than the actual amount, overreporting means reporting more than the actual amount. In science,…
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Eating in Israel for fuel and pleasure 2023
This is an update on my previous article eating in Israel for fuel and pleasure based on my experience in a Krav Maga training camp, one of the top travel experiences in my life. This time my expectations were high, but my focus was different. The first trip was for an Immersion camp, open to people of all levels. This means training was not super intense. In addition, more than 20 people were from my gym in Sydney, so I felt less social anxiety. This time, I attended an Advanced Instructor Training program, so I knew it would be more technical and intense. We were only 4 Australians attending. Based…
