Vitamins for Athletes: What You Need to Know

Why do we need vitamins?

Today we'll cover the most important vitamins — what foods they come from, and why the body actually needs them.

Let's start from the beginning. Vitamins are chemically diverse compounds that the body can't make on its own but absolutely needs to function properly. The word "vitamin" was first coined in 1912 by Polish scientist Casimir Funk, though the underlying idea goes back much further — the Greek physician Hippocrates, in the 5th century BC, was already telling patients with vision problems to eat liver. We now know liver is extremely rich in vitamin A. Vitamin C has a similarly well-known history: in the 18th century, British sea captain James Cook discovered that citrus fruit protected sailors on long voyages from scurvy, a disease caused by prolonged vitamin C deficiency.

How vitamins are classified

Vitamins fall into two broad groups:

• Fat-soluble vitamins — A, D, E, and K. These are found in fat-containing foods such as butter, milk, and eggs. The body stores them fairly well (mainly in the liver), so you can go without dietary intake for a few months without running into health problems.
• Water-soluble vitamins — vitamin C and the B-vitamin group. The body can't store these to any meaningful degree; any excess is simply excreted in urine. That's why it's better to split higher doses into smaller amounts spread across the day.

Vitamin C is probably the best known of them all. It's found mainly in citrus fruit, but also in smaller amounts in milk. Why is it so essential?

• It supports immune function.
• It's involved in a wide range of metabolic processes.
• Alongside vitamin E, it's a powerful antioxidant.
• It supports faster wound healing.
• It's essential for collagen formation.

How much should you take?

The standard recommended daily intake of vitamin C is 60 mg, or 100 mg for smokers. Athletes and anyone under significant physical or mental stress generally need noticeably more — hard-training bodybuilders sometimes take 1000–2000 mg a day. Doses that high could in theory cause health issues, though I've personally never come across a documented case of it happening. I take 500 mg a day long-term myself without any issues.

You'll find the recommended daily amounts of the other vitamins in the table below, but before that, a word of caution about the fat-soluble vitamins specifically, vitamin A above all — since, as mentioned, water-soluble vitamins are relatively easy for the body to clear on its own.

Vitamin A (retinol) has a recommended daily intake of just 0.5 mg, and long-term overdosing can cause serious problems: painful swelling, rashes, and hair loss. In extreme (and genuinely rare) cases, very high doses sustained over a long period can even be fatal. As with most things, moderation matters.

Now, where should your vitamins actually come from? A lot of people picture a pill swallowed on the way out the door in the morning when they hear the word "vitamin." That's not ideal. Think instead of fruit, vegetables, milk, eggs, and similar whole foods as your primary source — and keep in mind that cooking degrades vitamin content; vitamin C losses during cooking can run as high as 90%.