Our bodies become stressed by a combination of internal and external stressors. One such form of stress is oxidative stress, where an imbalance occurs between harmful free radicals and the body’s ability to neutralize them. Free radicals are very reactive, resulting in damage to cells, proteins, and DNA, and ultimately in chronic diseases and aging. Antioxidants, both those produced by the body and those taken in as part of the diet, can neutralize these free radicals and reduce oxidative stress and its subsequent damage to the body.
This article will discuss the science behind oxidative stress, how antioxidants lower the risk of disease, and how to incorporate more antioxidants into your diet in order to boost your health.
Oxidative stress is generated by an imbalance between the accumulation of free radicals (also known as reactive oxygen species) and the body’s ability to detoxify these species. Free radicals are produced as a by-product of metabolic reactions in cells. When maintained at a low concentration, free radicals play important roles within the organism. For example, they can be used for cell signaling or by the immune system to fight pathogens. However, if too many free radicals are present, then an imbalance occurs, giving rise to oxidative stress. This imbalance may result from processes within the body or external to the body, such as exposure to ionizing radiation.
Free radicals are, by their nature, incredibly reactive and can, therefore, react with a wide range of molecules within the body. These reactions are detrimental to the organism's health, causing damage to molecules. For example, oxidative stress can result in proteins undergoing changes to their structure, making them unable to function, or can react with DNA to cause mutations. These harmful effects of free radicals can, therefore, result in multiple diseases, including cancer, heart disease, neurological diseases, diabetes, and other chronic diseases. In addition, oxidative stress is thought to contribute to the body’s aging process.
Antioxidants are any substances that protect the body from free radicals through interacting with and neutralizing the free radicals. The human body has intrinsic defenses to maintain the balance of free radicals, these include:
In addition to intrinsic defenses, the body utilizes nutritional antioxidants introduced within the diet, these include:
Chronic inflammation is a factor associated with many diseases. While acute inflammation is necessary for fighting any foreign organisms infecting the body, chronic inflammation occurs when no stimuli are present and can be harmful to the body. The immune system produces free radicals as part of its efforts to destroy foreign organisms, however, when chronic inflammation is present, these free radicals can build up and cause an imbalance, resulting in oxidative stress.
Antioxidants play a key role in combating chronic inflammation by scavenging free radicals, increasing the activation of intrinsic antioxidant enzymes, and reducing the expression of pro-inflammatory molecules to inhibit the inflammatory response. Anti-inflammatory, antioxidant foods include turmeric, green tea, and blueberries.
Antioxidants further play a role in reducing the risk of chronic diseases, such as heart disease. Oxidative stress acts as a trigger for atherosclerosis (the build-up of substances such as fat and cholesterol on artery walls to form a plaque). The free radicals produced by inflammation at the plaque react with circulating LDL (low-density lipoproteins), which results in cell dysfunction, inflammation, and further plaque deposition. Antioxidants are, therefore, key to lowering the risk of heart disease.
For example, an intake of 1000 mg of flavonoids per day was associated with a 14 percent decrease in the risk of developing cardiovascular disease linked to atherosclerosis. Free radicals have also been linked to an increased risk of cancer due to their direct DNA-damaging effects. Antioxidants have been suggested as a way to reduce this risk of developing cancer by scavenging free radicals to reduce DNA damage.
Oxidative stress has been linked to neurodegenerative diseases, such as Alzheimer’s and Parkinson’s diseases. A high level of free radicals in the brain is thought to contribute to the death of vulnerable brain cells characteristic to these diseases and potentially also to the accumulation of toxic proteins in the brain, which further contribute to brain cell death. Dietary antioxidant consumption may, therefore, be a method through which to decrease the risk of developing neurodegenerative diseases. Although results from clinical trials are mixed, long-term cohort studies have found that those with a high intake of vitamins E and C (both antioxidants) have a reduced risk of dementia and Alzheimer’s.
The skin forms a barrier between our bodies and the outside world and, as such, is subjected both to internal and external factors that may cause damage. UV rays from the sun and pollution are two of the main factors that contribute to skin aging by triggering the increased production of free radicals. These free radicals attack structures forming the skin, such as collagen and elastin, causing fine lines, wrinkles, and dysfunction in the skin barrier, in addition to causing inflammation and increasing the risk of skin cancer. Antioxidants, such as vitamins C and E, can act as protective agents against skin aging by preventing free radical formation.
In addition to protecting the body by neutralizing free radicals, antioxidants can also contribute to the body protecting itself by boosting the immune response. For example, vitamin C is an antioxidant that improves the action of aspects of the immune system, such as immune cell proliferation, and has been shown to shorten the duration of infections, including the common cold.
The best sources of antioxidants are plant-based foods. These include:
To increase your consumption of antioxidants, try to incorporate 5 servings of fruit and vegetables per day into your diet. These should be different types of vegetables so as to introduce variety into the antioxidants that you are consuming. If possible, leave on the skin of the fruits and vegetables as these contain more antioxidants. Try to consume whole foods instead of ultra-processed foods (UPF), as UPFs contain little nutritional value and minimal antioxidants.
Oxidative stress resulting from an increase and imbalance of free radicals can be harmful to our bodies. Free radicals interact with other molecules within our bodies, causing damage to proteins and DNA. This can ultimately result in aging and the development of diseases, including cancer, cardiovascular disease, and neurodegenerative diseases. Antioxidants are key to neutralizing free radicals and have therefore been suggested to reduce the risk of developing many of these diseases and slowing signs of aging, such as the development of wrinkles.
Although we have antioxidants internal to our bodies, many essential antioxidants are obtained via our diets. Small changes to your diet can drastically increase the amount of antioxidants that you are consuming, lowering your risk of developing certain diseases and supporting healthy aging.
Take a proactive approach to healthy aging with Ezra. Our full-body MRI scans catch potential health issues early, helping you stay ahead of the curve. Book your scan today and invest in your health for a brighter tomorrow.
