Today I’m posting my 50th blog post!!! I feel like I should be writing about something a bit more exciting than vitamins, but unfortunately, my life just isn’t that exciting right now. Get up, eat, shower, lay on the couch, do sports nutrition homework, crutch around the house…you get it. Not too exciting.
We’re working on a vitamin and mineral section and I thought today I would speak about vitamins and minerals. I recently spoke about iron, and today I want to touch on the B-vitamins, magnesium and zinc. As an endurance athlete, we use many things to help us achieve our goals. Whether that be, hiring a coach, eating better, using better equipment (a better more aero bike, an aero helmet) or taking a supplement. Vitamins and minerals can indeed be classified as supplements, however in a later post I’ll speak specifically about ergogenic aid supplements, which are a bit different.
Vitamins and minerals are classified as micronutrients, and must be ingested daily. Our body’s cannot produce them and they do not provide a direct source of energy like macronutrients do. Remember, macronutrients are carbohydrates, fats and protein. So the next time you hear someone say, take this vitamin supplement (usually a B vitamin), it will give you energy, it actually will not, as vitamins are not a source of energy.
Vitamins-organic substances made by plants and animals. There are fat-soluble vitamins (A,D,E and K) and there are water-soluble vitamins (C and the B vitamins). Vitamins are co-factors and are called helper molecules. They regulate metabolic reactions that release energy from food and enable all biological processes. An example of a helper molecule is Vit. D. It helps the body absorb the mineral calcium. This is why you often see milk fortified with Vit. D.
Minerals-inorganic elements that come from the soil and water and are eaten or absorbed by the plants and animals you eat. Some minerals include, iron, calcium, chromium, copper, selenium and zinc. Minerals bind to proteins, and give it biological activity.
We need micronutrients in very small quantities. And what we don’t use, we excrete through our feces, urine, sweat, skin cell sloughing, menses and GI bleeding (lets hope not this one). One of my nutrition professors in undergraduate would always say multi-vitamins led to expense urine. And that for the most part holds true, even for athletes.
In the past 30 years, there have been multiple studies looking at whether or not athletes need vitamins and minerals in higher doses. Some studies show indeed, athletes do need to need higher intakes of vitamins and minerals, specifically the B vitamins. In addition, physical activity does increase the loss of micronutrietnts. That being said, as long as an athlete’s diet is sufficient, no extra supplementation is needed. Let’s look further.
The B Vitamins-B vitamins have an important role in the translation of energy from food to ATP. Carbohydrates require all the B vitamins to go through glycolysis and the TCA cycle. So, knowing that when you exercise, you need more ATP, we can say that the increased demands of energy from physical activity require adequate amounts of B vitamins to produce the needed ATP.
What would be adequate? Each of the B-vitamins is different in their RDA (recommended daily allowance). I’m not going to give you numbers as I’m sure they won’t mean much to you. That being said, athletes can consume double or triple the RDA and still be within the UL (upper limit) for safety. Most athletes are already doing that today, as B vitamins are seen in:
- Fortified soy milk and other soy products
- Fortified cereals and bread
One area to be aware of is athletes that are on fad diets, or trying to consume low calorie diets. These diets often cut large chunks out of a normal diet (no bread, no dairy, no meat) and then leave the athlete susceptible to a deficiency. Deficiencies can be observed with blood tests and sweat analysis, however both tests have their challenges.
In addition to the B Vitamins, we also looked extensively at research on magnesium and zinc. Not one research article concluded that any amount above the RDA for magnesium and zinc was warranted for athletes. Once again, the only time this wouldn’t be accurate was for athletes not getting enough minerals through their diet.
Magnesium-a mineral important in muscle and nerve function, bone growth, heart rhythm, and our immune system. Foods high in magnesium include spinach, nuts and seeds, fish, beans, whole grains, dairy, avocados and bananas
Zinc-a mineral important in muscle growth and immune function. Foods high in zinc include fish, beef, wheat germ, spinach, nuts and seeds, chocolate, fortified cereals, beans and pork/chicken. Zinc is also more readily absorbed from animal products.
To sum up:
- Athletes do need more vitamins and minerals than the average person as they are losing more in sweat/urine and needing more in the production of ATP and other physiological functions
- As long as athletes are consuming enough variety of foods and calories, they should be getting enough vitamins and minerals from their diet, and do not need an additional supplement. There has been really no conclusive data in the last 30 years that extra supplementation is important.
- Blood tests and sweat tests can be done to determine an athletes plasma and serum concentrations of the vitamins and minerals. Before a blood test, athletes must not have been exercising for at least 8 hours.
- An athlete needs to speak with their physician about getting a blood test, and the results of the blood test. They are the only one’s qualified to assist an athlete in this matter.
- If you’d rather have expensive urine and take a multivitamin just in case, that is your choice but you should still speak with your physician first as there are toxic levels of vitamins and minerals. And personally when I’m in a heavy training load (15 hours+), I will usually take a vitamin/mineral supplement and take the expensive urine.