Antioxidants in food

Antioxidants in food is a group of compounds that neutralize free radicals, using dietary sources for athletic performance and recovery.

For a broader context, see the complete guide to proper nutrition — a fundamental guide from the expert team at Sport Zona.

What it is

Antioxidants are a class of compounds naturally present in many foods that play a critical role in protecting the body from oxidative stress. This stress occurs when there is an imbalance between the production of reactive oxygen species (free radicals) and the body's ability to neutralize them. Free radicals are unstable molecules with an unpaired electron that seek to bond with other molecules, damaging cellular structures like DNA, proteins, and lipids.

Dietary antioxidants vary in their chemical structure and include vitamins (such as vitamin C and E), minerals (such as selenium and zinc), as well as phytochemicals like polyphenols and carotenoids. They work together, often synergistically, to provide comprehensive protection. For sports nutrition, adequate antioxidant intake is essential due to the increased production of free radicals during intense physical exertion.

How it works

The mechanism of action of antioxidants is related to their ability to donate electrons to free radicals without becoming unstable themselves. In this way, they stabilize free radicals, converting them into harmless molecules and preventing chain reactions of damage within cells. Some antioxidants directly neutralize free radicals, while others support the body's enzymatic systems that perform this task.

Sports activity significantly increases metabolic activity and oxygen consumption, leading to greater production of free radicals such as superoxide anions, hydroxyl radicals, and hydrogen peroxide. Antioxidants help to:

• Protect muscle cells from oxidative damage.
• Reduce inflammatory processes after training.
• Support tissue repair and reduce muscle soreness.
• Optimize immune function, which can be compromised by intense training.

Why it's important for athletes

For athletes, adequate antioxidant intake is critical for maintaining health, recovery, and optimizing performance. Intense training increases oxidative stress, which can lead to fatigue, muscle damage, and impaired recovery. Studies show that a diet rich in antioxidants can mitigate these negative effects. For example, the recommended intake of vitamin C for active athletes can reach 500-1000 mg per day, significantly higher than the general recommended daily allowance (75-90 mg) for the general population, to support immune function and reduce oxidative stress. Vitamin E, an important fat-soluble antioxidant, is recommended in doses of 200-400 IU (134-268 mg) in some heavy training regimens.

The International Society of Sports Nutrition (ISSN) emphasizes the importance of phytonutrients from fruits and vegetables, which provide a wide spectrum of antioxidants. Guidelines often recommend an intake of 5 to 9 servings (approximately 400-720 grams) of fruits and vegetables daily for athletes, as this approach provides antioxidants as well as other essential nutrients. Instead of relying on high doses of isolated supplements, which can have unforeseen effects or even suppress training adaptations, the focus is on a balanced diet rich in whole foods.

Related concepts

• Polyphenols — These are a large group of phytochemicals with powerful antioxidant properties, which are key components of antioxidants in food.
• Whole foods — These are the best source of natural antioxidants, offering a synergistic effect of various nutrients.
• Antinutrients — Some antinutrients can affect the absorption of antioxidants or interact with their function.
• Lectins — Lectins are proteins that can affect the bioavailability of certain nutrients, including antioxidants, from plant sources.