There is much discussion in online forums and traditional media about the benefits of antioxidants. But, where’s the best place to find them? This article will answer some of the most commonly asked questions about antioxidants and which foods contain the most powerful ones.
What are antioxidants?
One of the internal threats to our bodies comes from chemicals known as ‘free radicals’. These can damage the cells of the body and even alter strands of DNA1. These are produced in the body during the process of transforming food into energy; thus, they are naturally occurring. However, they can also be generated through less natural means, such as exposure to sunlight, cigarette smoke, and air pollution2.
Free radicals take the electrons from other nearby atoms, which can have a range of negative impacts on the body1. Excessive amounts of free radicals in the body can cause a condition called ‘oxidative stress’, which may lead to chronic diseases3. However, the body does produce molecules that combat free radicals, called ‘antioxidants’1. These can also be found in certain foods (see below). Antioxidants work by donating electrons to free radicals without becoming starved of electrons themselves, meaning that the free radicals no longer sap from other cells in the body1.
There are a great many different types of antioxidant chemicals. The most commonly known include vitamin E, vitamin C, and beta-carotene, with others including lipoic acid, flavonoids, phytoestrogens, phenols, etc.1,3 The majority are naturally occurring and can be obtained from food, meaning that maintaining a balanced diet can keep you free of the risk of oxidative stress. Nonetheless, you can help to boost your body’s defenses by taking on certain foods that are rich in antioxidants. It should be noted, however, that different antioxidants have varying properties, meaning that taking on a lot of one type cannot do all the work1. The key is to include a variety of antioxidants in your diet.
What are the health benefits of antioxidants?
Oxidation stress brought about by a high quantity of free radicals in the body has been linked to many health conditions, including cancer, blindness, and heart disease1. However, research into the benefits associated with consuming antioxidants to reduce these risks has been mixed. Some have shown that antioxidant supplements don’t protect against chronic diseases after all4. One research project even illustrated that certain supplements actually increased the risk of lung cancer in smokers5.
That being said, there are proven health benefits to the consumption of antioxidants. For example, one study demonstrated a 24% decrease in cardiovascular mortality levels amongst women taking a naturally-sourced vitamin E supplement6. Vitamin E has also been shown to lower the risk of coronary heart disease among sufferers of type 2 diabetes7, suggesting potential benefits associated with specific groups of people. Furthermore, benefits have been found among people with pre-existing cardiovascular concerns8.
Cancer risk has been proven to be reduced in men taking a cocktail of mixed antioxidants, though the same is not true of women9. But, again, pre-existing conditions may be a factor, as shown in a study that demonstrated significant reductions in cancers of organs such as the colon and lungs among patients with skin cancer, when they were taking antioxidants10.
Additionally, antioxidant supplements have been found to lower the chance of developing age-related ocular deterioration in people who are more susceptible to such conditions11. Research has demonstrated favorable results in certain antioxidants protecting vision12; although, conflicting studies also exist, particularly if one takes only one antioxidant supplement, in which case there is limited evidence of positive impacts regarding vision13.
Cognitive improvements have been seen when people take antioxidant supplements for a significant period of time (e.g., at least 15 years)5; however, evidence regarding the notion that antioxidants can reduce the risk of developing dementia is inconclusive14.
Essentially, it is undoubtedly true that the balance of antioxidants, vitamins, minerals, and fiber in fruits and vegetables is beneficial to human health1. But, unfortunately, it is unlikely that antioxidant supplements can provide the same benefits. Therefore, it’s essential to ensure that you are eating foods rich in antioxidants (see below).
Which are better: antioxidant-rich foods or antioxidant supplements?
The likely reason why research shows limited health benefits regarding antioxidant supplements is because they typically work best when taken in combination with other vitamins and nutrients. Therefore, having them naturally from foods that are rich in a variety of antioxidants is probably the best way to get them into your system.
By way of example, a cup of fresh strawberries includes approximately 80mg of vitamin C (an antioxidant). In comparison, a 500mg of vitamin C supplement does not contain the polyphenols (plant chemicals) that work alongside the antioxidant1. Thus, eating strawberries may have more substantial health benefits than taking supplements.
The type of antioxidant is also important. For instance, there are eight different chemical forms of vitamin E in foods, while vitamin E supplements tend to only incorporate one of these types (which is alpha-tocopherol)2. This is further evidence to support consuming antioxidants through foods. Indeed, higher intakes of fruits, vegetables, and legumes that are rich in antioxidants have been shown to significantly lower the risk of diseases associated with severe oxidative stress, such as cancer and cardiovascular concerns15.
Which foods contain which antioxidants?
The following is a list1 of antioxidants and which foods are particularly rich in them:
Vitamin E: Almonds, avocados, Swiss chard, beets, mustard, peanuts, red peppers, turnips, sunflower seeds, and boiled spinach.
Carotenoids: Asparagus, beets, carrots, bell peppers, apricots, broccoli, mangos, turnips, oranges, cantaloupes, pink grapefruit, winter squash, pumpkins, peaches, tangerines, yams, tomatoes, watermelons, and spinach.
Selenium: Fish, beef, poultry, shellfish, barley, Brazil nuts, and brown rice.
Vitamin C: Cantaloupes, grapefruit, broccoli, turnips, beets, collards, honeydew melons, Brussels sprouts, mustard, papaya, lemon, kale, kiwi, strawberries, yams, bell peppers, tomatoes, and oranges.
Phenolic compounds: Red wine, tea, betties, cocoa, apples, onions, grapes, peanuts, white wine, blueberries, and strawberries.
Zinc: Oysters, sesame seeds, lentils, chickpeas, cashews, beef, poultry, shrimp, and pumpkin seeds.
Antioxidants help to protect your body against free radicals, which cause damage to cells and genetic material. They do this by donating electrons to the free radicals, thereby stopping them from sourcing electrons from other atoms in the body.
There are notable health benefits of antioxidants. These include reducing the risk of cardiovascular diseases, cancer, eyesight deterioration, and degenerative cognitive function. However, antioxidant supplements do not necessarily allow for these health benefits, as has been demonstrated through much empirical research. Instead, it is better for your health to consume a balance of foods that are rich in antioxidants, as this will allow a broad spectrum of not only antioxidants, but also other elements that work together to bring health advantages.
In general, the foods that are best if you want to take on a high quantity and wide range of antioxidants are fruits and vegetables. Most notably, the following items all contain more than one highly beneficial antioxidant:
Overall, it is always advised to maintain a balanced diet that incorporates a high proportion of fresh, unprocessed foods. Legumes, vegetables, fruit, and seeds are all particularly beneficial to human health.