As people get older, they develop chronic conditions such as Alzheimer’s disease, arthritis, cataracts, cancer, heart disease, diabetes, and dementia. Therefore, it raises the question of why these diseases usually develop as a person ages? How does aging affect our bodies? In this blog, we will briefly discuss the concepts of Free Radicals, Oxidative Stress, and Antioxidants in simple language and attempt to find some answers to these questions.
What is a Free Radical?
We are aware that all matter is made up of atoms. It consists of a nucleus containing protons and neutrons, and electrons orbiting in layers or shells around the nucleus. In every shell, electrons must exist in pairs. When the outermost shell lacks electrons, the electrons are not perfectly paired. Atoms of this type “react” with neighboring atoms to “steal” electrons and have perfect electron pairs.
Atoms that have exactly paired electrons are called “stable” atoms; in comparison, free radicals are atoms or molecules which contain unpaired electrons and are characterized as “unstable.” An important aspect of free radicals is that they vary in chemical composition.
Here is the atom connection in our body. Body organs are made up of tissues, which are made up of the most basic building block called cell, which in turn is made up of atoms.
Why are Free Radicals harmful to our bodies?
As “unstable” atoms react with neighboring “stable” atoms, they “steal” electrons from them and become stable atoms themselves, while the atoms that lost the electrons become unstable. This kicks off a continuous process of reactions (or oxidation) between unstable and stable atoms. So far so good, however as we age, there may come a time when unstable atoms cannot be “neutralized” as fast as they are created in our body thus creating free radical overload. This causes severe oxidative stress, which means there are too many free radicals in the body interacting with other molecules. This is where things start to go wrong in our bodies.
Oxidative stress damages body cells and hence various tissues and organs. It may damage fatty tissues, DNA, and proteins in our bodies. It is at this point that chronic and degenerative diseases take root in the body. These adverse changes are gradual and asymptomatic initially, but they progressively become more severe as we “age”. As a result of this, people may age faster, and develop cancer, cataracts, and various disorders. Further, oxidative stress can also induce complications in people already suffering from chronic diseases.
How are Free Radicals created in our bodies in the first place?
Free radicals are continuously created in our bodies either as a result of metabolic processes (a metabolic process is a chain of chemical reactions in our body) internal to our body or due to external factors.
There are two critical metabolic processes that take place in our body cells. One is responsible for building glucose molecules from the food we eat. The other is responsible for breaking down glucose molecules to release energy that keeps us alive. Free radicals are a byproduct of the process of breaking down of glucose molecules.
Free radicals may also be created due to exposure to pollution, chemicals, radiation, etc. Sunscreen lotions, non-stick cookware, microwave popcorn bags, takeaway containers, Ziploc bags, paints & varnishes, raincoats, radiation, x-rays, cigarette smoke, and items touted as heat-resistant or waterproof are a few examples of everyday things which very likely contain chemicals that can harm our body.
How Free Radicals can be neutralized?
As we discussed above, oxidative stress can cause serious harm to our body cells, tissues, and organs leading to various chronic diseases. There are various compounds, vitamins, and minerals that can act as “antioxidants” and prevent or limit this damage.
An antioxidant is not really a substance; it is just a property of the aforesaid substances. We loosely refer to these substances as antioxidants.
Antioxidants donate an electron to free radicals, hence preventing them from reacting with other atoms without becoming themselves free radicals. This reduces oxidative stress and in turn limits damage to our bodies.
It is important to remember that antioxidants have different chemical compositions, just as free radicals do. Thus, a single antioxidant cannot neutralize every free radical. We need antioxidants with varied chemical compositions in our diet to be able to neutralize as many free radicals as possible.
Antioxidants are either made within our body (endogenous antioxidants) or are obtained from diet and supplements (exogenous antioxidants).
Alpha Lipoic Acid, Catalase (CAT) and Coenzyme, Glutathione Peroxidase (GPx), Glutathione (GSH), and Superoxide Dismutase (SOD) are the endogenous antioxidants. As we age, the production of these antioxidants declines in our body thus initiating degenerative diseases.
On the other hand, there are thousands of substances that can act as exogenous antioxidants. These include vitamins, minerals, chemicals, and various phytonutrients (chemical compounds found in plants).
There are approximately 25000 phytonutrients, classified and grouped extensively. Some common phytonutrients are Lignans, Resveratrol, Carotenoids, Curcumin, Ellagic Acid, and Flavonoids.
The following is an illustrative list of antioxidants to highlight their importance in our health. We recommend consulting qualified nutritionists for the most recent information regarding antioxidants because a lot of research is still being conducted to discover their benefits.
Few important Antioxidants
Allicin
This chemical compound may help in lowering blood glucose, blood pressure, and bad cholesterol. It may also provide protection against various forms of cancer.
Food Sources: Garlic, onion
Beta-carotene
This carotenoid is present in orange or red color fruits and vegetables. The body converts it into Vitamin A which is responsible for the growth of cells and good health of various body organs. It may also prevent macular degeneration and improve eye vision.
Food Sources: Brightly colored yellow, orange, and some green fruits and vegetables such as carrots, tomatoes, red and yellow bell pepper, pumpkin, spinach, kale, lettuce, broccoli, sweet potatoes, papaya, mangoes, and oranges.
Lutein
This carotenoid fights off free radicals, reduces oxidative stress, prevents macular degeneration, protects the eye from sunlight damage, and improves vision.
Food Sources: Kiwi fruit, grapes, spinach, kale, zucchini, corn, pepper, orange, and egg yolks.
Lycopene
It is also a type of carotenoid. Similar to beta-carotene, it gives the red color to fruits and vegetables. It prevents damage to body cells, improves skin health, and may prevent cancer.
Food Sources: Tomatoes, red carrots, watermelon, papaya, red guava, prink grapefruits.
Resveratrol
This polyphenol may be useful in conditions of high cholesterol, cardiovascular diseases, and cancer.
Food Sources: Grapes, blueberries, raspberries, peanuts, grape wine, juices.
Glutathione
It builds and repairs damage to body tissues and synthesizes various proteins in the body. It may slow down aging and help in various medical conditions related to the liver and heart.
Food Sources: The body synthesizes Glutathione. It can also be found in fish, poultry, spinach, mustard leaves, okra, broccoli, kale, brussels sprouts, asparagus, cauliflower, garlic, onions, turmeric, and avocados. Vitamin C-rich and Selenium-rich foods too contain Glutathione.
Quercetin
It is a flavonoid found in plant-based foods. It is anti-inflammatory and may be useful in the treatment and prevention of cancer, diabetes, and cardiovascular diseases.
Food Sources: Red grapes, red wine, green tea, apples, berries. Citrus fruits, green leafy vegetables, onions.
Curcumin
Curcumin is a very powerful antioxidant. It is anti-inflammatory and also very effective in dealing with oxidative stress which is the root cause of many chronic diseases. Curcumin is helpful in improving insulin resistance, improving cholesterol by lowering LDL and boosting HDL, and managing blood pressure, arthritis, and anxiety.
Food Sources: Turmeric
Vitamin C (L-ascorbic acid)
It limits the damage caused by free radicals, helps in the prevention of many chronic diseases, and boosts immunity. It also repairs body tissues and helps improve Glutathione levels in the body.
Food Sources: This is present in foods and supplements. Citrus fruits such as oranges, kiwi, papaya, strawberries, peppers, broccoli, potatoes.
Vitamin E
Boosts Glutathione levels in the body. As an antioxidant, it may prevent cell damage, reduce the risk of certain cancers, protect the thyroid, reduce symptoms of asthma, and protect against cardiovascular diseases.
Food Sources: Poultry, fish, cottage cheese, brown rice, and foods grown in soil.
Manganese
It is needed for the proper functioning of the brain and nervous system.
Food Sources: Whole grains, seeds, legumes, beans, nuts, leafy greens.
It is very clear that antioxidants play a very important role in our health by combatting the effects of free radicals. Hence, it does make sense to include a variety of foods in our diet plan to enjoy a healthy life in our advanced years.