Antioxidants Overview
Antioxidants are any compounds that help prevent cell damage in the body. One of the common reasons for cell damage is oxidation, where an atom or a molecule loses electrons.
While oxidation is useful for a few processes, excess oxidation leads to cell damage. The use of antioxidants is to regulate the level of oxidation in the body.
Depending on whether the antioxidants are soluble in water or fat (lipids), they are classified into two broad categories:
- Hydrophilic antioxidants (water-soluble)
- Lipophilic antioxidants (fat-soluble)
Antioxidants At The Molecular Level - Getting Technical
There are four basic levels of defense that all antioxidants have:
- Neutralizing free radicals by donating their own electrons
- Proactively searching and removing free radicals before they cause damage
- Self-repair and regulation of the internally produced antioxidants
- Adapting themselves to the body’s changes
Inside the body, the following factors determine antioxidant absorption and utilization:
- The pH level of the gastrointestinal tract
- The size of the antioxidant molecules
- The oxygen tension in blood
- The types of gastrointestinal bacteria in the tract
The effectiveness of antioxidants depends on the internal environment they survive in.
Generally, larger molecules of antioxidants are broken down by the gut bacteria to help them enter the cell membranes.
The liver produces a few very important antioxidants. The cell membranes absorb some, while a large part is excreted out through urine.
Did You Know?
Have you heard of the famous egg or chicken question? The debate over whether the egg or the chicken came first to the world is never-ending. Until recently, scientists debated whether antioxidants were produced before or after the earth received oxygen through photosynthesis.
One may assume that microbes developed the ability to produce oxygen through photosynthesis first. This caused oxidative stress, and their bodies adapted themselves to produce antioxidants.
This is not the case, though!
According to this 2017 article, an anaerobic bacterium (oxygen-free bacterium) started producing an antioxidant called ergothioneine before it started the process of photosynthesis.
If not for neutralizing the effects of oxidation, what was the use of this antioxidant? Researchers are still trying to find out the answer to this question.
Why Do Humans Need Antioxidants?
Free radicals are unstable molecules that contain an unpaired electron. Because of this, they are highly reactive. Free radicals start taking electrons from the cells in your body and damages them in this process.
Free radicals are found in the air you breathe in, in the water you drink, in the foods you eat, and even in certain medications!
Antioxidants help by sacrificing/giving up their own electrons to the free radicals, thereby neutralizing them. Instead of damaging your cells, the free radicals damage the antioxidants, keeping you safe.
When your body does not have antioxidants, your cells are damaged faster because of free radicals, and this causes a variety of physical issues, including:
- Cancer
- Parkinson’s disease
- Alzheimer’s disease
- Cardiovascular problems
- Inflammatory diseases
- Collagen loss leading to signs of aging in skin
- Protein oxidation leading to aging
Genetic Association
GPX1 and Antioxidant Needs
Selenium is an important antioxidant that is needed for the healthy functioning of the body. Many enzymes in the body that fight free radicals are affected by how much selenium you get in your food.
Certain variations in the proteins GPX1 because of inadequate selenium intake are associated with increased cancer risk. In the rs1050450 SNP of the GPX1 gene, a minor allele ‘A’ increases your risk of developing cancer when your dietary selenium levels are low.
PON1 and Antioxidant Needs
Lycopene is a type of carotenoid that gives the red color to fruits and vegetables. This is also a very important antioxidant.
The PON1 gene helps produce the PON1 enzyme to protect against the oxidation of Low-Density Lipoprotein (LDL). LDL oxidation results in risks of atherosclerosis, heart attacks, and strokes.
The Q192R (denoted by rs662) is a polymorphism in the PON1 gene. The presence of the TT allele can imply lower or decreased levels of PON1 enzyme activity. The higher the PON1 enzyme activity, the lower is the risk for heart disease.
Non-genetic Factors Affecting Antioxidant levels
Unhealthy food habits - Most of the antioxidants required by your body can be obtained by including various fruits, vegetables, and other plant-based ingredients regularly. If you depend on restaurant takeaways or packaged and frozen foods for your meals, you may be at a higher risk for developing antioxidants deficiency.
Harvesting and handling of fruits and vegetables - Certain methods of harvesting and handling fresh fruits and vegetables can cause a reduction in the antioxidant levels in these produces. Consuming these fruits and vegetables will not give you your recommended values of antioxidants.
Cooking methods - According to a study boiling and pressure cooking the vegetable bring down the antioxidant levels. Opt for gentler cooking methods like steaming and quick frying instead.
Symptoms Of Excess Antioxidants
It is difficult to get an overdose of antioxidants with just food sources. However, it is possible to overdose when you are using antioxidant supplements. Here are some of the symptoms of excess antioxidant consumption:
- High doses of beta carotene are associated with an increased risk of lung cancer in those who smoke.
- High doses of vitamin E supplements can cause prostate cancer and bleed in the brain.
- High doses of vitamin A can lead to liver damages.
- Some studies suggest consuming excess antioxidants can make existing symptoms in cancer patients worse.
- Selenium overdose leads to nausea, bad breath, and various kidney and heart problems.
- Excess antioxidants can interact with certain medications that you take. Talk to your healthcare provider about recommended levels.
Symptoms Of Antioxidant Deficiency
A 2018 study analyzed the intake of 10 antioxidants. The antioxidants under consideration were beta carotene, alpha-carotene, beta-cryptoxanthin, lutein, lycopene, zeaxanthin, selenium, zinc, and vitamins C and E.
The study concluded that those deficient in these ten antioxidants had lowered anti-inflammatory activities and lowered HRQOL - Health-Related Quality Of Life. It includes factors needed for physical, mental, social, and emotional quality of life.
Oxidative stress, over time, can damage healthy cells in the body. This can result in increased risks of:
- High blood pressure
- Diabetes
- Neurodegenerative diseases
- Cancer
- Skin diseases
- Premature aging of the skin
- Inflammatory diseases
- Hardening of blood vessels (atherosclerosis)
## Recommendations To Get The Right Amounts Of Antioxidants
**Include a variety of vegetables and fruits** - Vegetables and fruits are very rich sources of different antioxidants. One of the best ways to prevent antioxidant deficiency is to include colorful fruits and vegetables in your diet. Studies show that fresh fruits and vegetables bring down your risk for developing several diseases apart from keeping you fit.
**Prefer food-based antioxidants over supplements** - Unless you have been advised specifically, stay away from supplements and change your food habits to increase your antioxidant intake.
**Know how your genes affect you** - If you are genetically prone to requiring more antioxidants than normal individuals or at a higher risk for developing certain diseases because of antioxidant deficiency, plan your food choices right.
**Supplement antioxidants with caution** - While supplements can easily cause an overdose, supplements can also interact unpleasantly with certain medications you consume.
**Change your cooking methods** - Your cooking methods matter a lot. Choose healthier cooking options like broiling, steaming, and quick frying on a flat pan instead of boiling and pressure cooking.
## Summary
1. Antioxidants are compounds that help prevent cell damage. There are 1000s of individual antioxidants available in nature.
2. While most antioxidants are obtained from food sources, few very vital ones are produced in the body.
3. Antioxidants bring down the risks of several diseases and keep you younger for a longer time.
4. Antioxidant overdose is rare and occurs only upon consuming supplements. Antioxidant deficiency can lead to a lowered Health-Related Quality Of Life (HRQOL).
5. Some people can be genetically inclined to absorb lesser quantities of antioxidants than others. Such individuals may need to compensate with supplements.
6. For healthier individuals, it is recommended to get the dose of antioxidants from food rather than from supplements.
References
https://www.hsph.harvard.edu/nutritionsource/antioxidants/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3249911/
https://www.nccih.nih.gov/health/antioxidants-in-depth
https://pubmed.ncbi.nlm.nih.gov/18630141/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3614697/
https://www.ahajournals.org/doi/10.1161/circ.136.suppl_1.12351
https://www.nccih.nih.gov/health/antioxidants-in-depth
https://pubmed.ncbi.nlm.nih.gov/24915343/
https://www.sciencedaily.com/releases/2009/04/090415163730.htm
https://www.health.harvard.edu/staying-healthy/understanding-antioxidants
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3249911/
https://www.cbc.ca/news/health/antioxidant-supplement-overload-can-be-hazardous-1.1412993
