In sports nutrition many half-truths circulate concerning supply recommendations for Vitamin mineral materials. Here is the opinion of nutrition expert Paolo Colombani.
Requirements and intake in sports
Text by: Dr. Paolo Colombani
When it comes to nutrition, experts keep coming up against two questions: Which nutrients are the most important for me or my situation? Which ones do I need, which ones less? This is no different with minerals. However, the answers to these questions do not always turn out as expected. The question about the more important or less important nutrients is understandable. After all, there is a ranking list for (almost) everything: the fastest cars, the best racing bikes, the fastest marathon runners, the fastest egg boilers. Everywhere there is a “better” and therefore automatically also a “less good”. So why shouldn’t there be a ranking of nutrients based on their “performance” or importance?
Nutrients do not act in isolation
But when it comes to nutrients, the situation is different. The question of classification according to their importance is based on a false premise. This is because nutrients never work on their own or against other nutrients, but always only together with other nutrients in a complex metabolic system. It is like the different instruments in a large symphony orchestra. Only the presence of all the instruments specified by the piece of music makes the desired sound experience possible. No instrument is more important than the other. This is also true for nutrients. There are no more or less important nutrients, whether vitamins, minerals or other nutrients. They are all needed and are all equally important for the optimal functioning of the metabolism. This is a basic definition of nutrients. In a large symphony orchestra, however, the instrumentation of individual voices can be a challenge. If a bassoon is required, it may not be more or less important than the other instruments. But perhaps it is no longer trendy to play the bassoon in a country and therefore difficult to find bassoonists. Accordingly, there are situations in which sportsmen and women have more trouble absorbing a sufficiently high amount of a nutrient. This nutrient is therefore not more or less important. But it is more difficult to ensure a sufficient supply.
Needs and intake in sports
Many myths and half-truths circulate in sports nutrition. Higher intake recommendations for vitamins and minerals are certainly among them. The main problem is that many confuse the recommended intake with the need. The requirement is the amount of the nutrient that the metabolism needs. The recommended intake, on the other hand, is the amount we should take to meet the need. These are two completely different things. The requirements vary from person to person. A wrestler weighing 110 kilograms undoubtedly has a higher requirement for minerals and vitamins than a marathon runner weighing half as much and 55 kilograms. So that a separate recommendation does not have to be made for each person, the recommendations for the intake of minerals or vitamins are set so high that they are correct for practically all healthy people in the population. This recommended intake is calculated, in simple terms, from the average requirements plus a decent safety margin. For magnesium, the effective requirement in the total healthy adult population is an average of 165 mg per day, with a range of 110 to 240 mg (1). The magnesium requirement may therefore vary by 100% in individual cases (this range of variation is different for each nutrient). The recommended intake has been set at 300 mg for women and 350 mg for men. If a woman with a low requirement of 110 mg per day takes exactly the amount recommended for women, she will take 190 mg more than she needs. Even a man with a high requirement of 240 mg would still take 110 mg more than he needs when taking the recommended intake. Therefore, it is not necessary to know exactly how much you actually need. Because no matter where it is, taking the recommended intake ensures that all needs are covered because of the safety margin. Athletes may have a slightly higher need than non-athletes due to their activity. However, the requirement is not so high that it exceeds the recommended intake for the general population. On the contrary: the consensus is that the currently recommended intake of all minerals and vitamins already contains such a high safety margin that it is almost certainly correct for all healthy athletes. In other words: The recommended intake of minerals and vitamins for the general population also applies to those who participate in sports (2-4). Mineral or vitamin supplements do not therefore have to be prioritized in sports.
Special situations in sports
The recommended intake of minerals and vitamins can be achieved without any problems, even for athletes, by choosing a variety of foods according to the usual recommendations of the food pyramids (3). Only when the diet is rather one-sided or does not cover the increased energy requirement through exercise can problems arise with one or the other nutrient – this also applies to minerals. To what extent this applies in individual cases, however, can only be assessed by examining individual nutritional behavior. In the following situations, however, it could in principle become critical:
Low calorie intake:
Anyone who consciously or unconsciously eats little and thus takes in less energy has an increased risk of an insufficient supply of nutrients. The minerals are not an exception. However, if you consciously consume low amounts of energy (e.g. for a desired weight loss), you can act prophylactically. Taking a multi-vitamin as a guarantee for an adequate micronutrient supply is certainly not wrong in this situation. However, one could also use a meal replacement instead of self-made dietary meals where one never really knows how many micronutrients they provide. A product called a “meal replacement” must provide one third of the recommended amount of all vitamins and minerals per meal.
The incidence of gastrointestinal problems in runners and cyclists is between 30 and 65% (5), depending on the survey. If the intestine is affected, e.g. diarrhea or an inflammatory disease of the intestine, the absorption of minerals in the intestine may be impaired. This situation certainly requires professional clarification and the priority would be to get the intestinal problems under control.
The trend towards vegetarian and vegan nutrition continues and seems to be gaining ground. But the higher the portion of vegetable food is, the more materials there are which obstruct the absorption of certain mineral materials. This applies in particular to zinc or calcium (6). Besides iron or iodine can become problematic, if one does without meat, fish as well as iodized salt or one generally only little salt takes (7).
Women: Iron can be critical more often in women than in men, especially in women of childbearing age (8,9). The main reasons are the 50% higher iron requirement due to menstruation, coupled with the usually lower energy requirements of women.
To avoid a deficient supply of minerals, the first and classic tip would be: Eat enough and variety. This tip is one that many people are almost no longer able to follow. It says nothing new and is not specific enough to be put into practice. The second tip is somewhat more concrete: If you are not sure whether your mineral intake is sufficient, you should have this clarified by a specialist. But not all of those who are unsure want to go through the effort of a consultation. For them, the last tip is therefore the simplest way, even if nutrition experts are reluctant to give it and it would not be necessary at all: Take dietary supplements. However, one basic rule must be followed. The total amount of a mineral or vitamin that we take via dietary supplements (and fortified foods) should not be much more than 100% of the recommended intake. This is easy to check, because dietary supplements must by law state the daily dose as a percentage of the recommended intake “NRV”. It then says on the package, for example: One tablet per day corresponds to 25% NRV magnesium. Anyone who clearly exceeds the 100% NRV will quickly reach the maximum amounts above which health side effects are possible. That is why it is better to choose food supplements that are moderately dosed and do not try to pretend that there is no additional benefit through excessive amounts.
1. EFSA Panel on Dietetic Products NaA. EFSA J., 2015; 13: 4186
2. Volpe SL. Clin. Sports Med., 2007; 26: 119–30
3. Mettler S. et al. Int. J. Sport Nutr. Exerc. Metab., 2009; 19: 504–18
4. Maughan RJ, Shirreffs SM; J. Sports Sci., 2011; 29: S1
5. Coleman N. Curr. Sports Med. Rep., 2019; 18: 185–7
6. EFSA Panel on Dietetic Products NaA. EFSA J., 2014; 12: 3844
7. Craig WJ, Mangels AR. J. Am. Diet. Assoc., 2009; 109: 1266–82
8. Lopez A. et al. Lancet, 2015; 387: 907–16
9. Camaschella C. N. Engl. J. Med., 2015; 372: 1832–43
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