Please DO NOT DELETE this page.

Blog //
  • Nutrition
//

Are antioxidant supplements good, bad, or completely unnecessary?

12 March, 2015
Antioxidants

What are antioxidants?

Antioxidants can fight against free radical damage, which helps us to stay healthy and live longer. As a result, many people are taking antioxidant supplements as part of their diet. However, despite their many health benefits, scientific studies have proven that artificial supplements aren’t necessarily the answer. So, below we will look at what’s good and bad about antioxidant supplements and whether they’re needed.

Free radicals and the process of oxidation in the body

When the oxygen that you breathe in through your lungs is metabolised into your blood, it creates unstable molecules known as ‘free radicals’, these are destructive molecules which can cause damage to your DNA and cell membranes. While the body does need some free radicals to function, if there are too many built up in a person’s system then the damage can become irreparable and may lead to diseases such as cancer, cardiovascular disease, liver disease, and many others.

Antioxidants are naturally found in a number of foods and these cells can, to some extent, prevent free radicals from damaging your cells by neutralising them. These antioxidants can be found in vitamins A, C and E, in the minerals selenium, zinc and copper, and can also be found in phytochemicals from plants, fruits and vegetables.

What’s good about antioxidant supplements?

They help fight against ageing, cancer and chronic diseases

Antioxidants minimise damage to your cells from oxidants (aka free radicals), and can help fight against ageing, cancer, and chronic diseases like cardiovascular disease. This has been proven by a study published in January 2008, which showed that taking antioxidant supplements like selenium could have ant-carcinogenic effects.

They remain safe from damaging free radicals

Antioxidants also don’t run the risk of getting damaged or turning into free radicals themselves when reacting with free radicals. 

What’s bad about antioxidant supplements?

They prevent your body from making its own antioxidants

Your body makes its own natural antioxidants, which can actually be prevented if you take antioxidant supplements. Although the supplements provide you with antioxidants, they can’t balance the loss of your own antioxidants which are produced naturally rather than artificially.

They can’t prevent or cure all your ailments

Taking vitamin C won’t prevent you from catching a cold, and taking vitamin E won’t prevent you from aging or getting heart disease. Vitamin supplements also can’t prevent you from getting mental illnesses like schizophrenia or bipolar disorder. While it has been proven that antioxidants can decrease the likelihood of you contracting one of these diseases, it by no means guarantees you won’t develop them anyway.

They act as pro-oxidants when taken at high concentrations

A research study published on 9 April 1998 found that vitamin C supplements can act as a pro-oxidant when taken at high concentrations. This is because vitamin C reacts not only with free radicals but also with other molecules in the body. One of these reactions is the Fenton Reaction, which was described in a study published in June 1999. It produces extra free radicals, so the antioxidant supplements become ineffective at stopping the production of free radicals. Artificially produced antioxidants are particularly ineffective against these free radicals as compared to natural antioxidants produced by the body.

They also harm your body when taken in high doses

If you don’t have a vitamin deficiency and you take high doses of vitamin A, D, E or K (fat-soluble antioxidants that can be stored in the body) for a long time, they could become toxic and harm your body. Water-soluble antioxidants can also give you side effects if taken in large doses, e.g. vitamin B6 can cause nerve damage, whereas vitamin C can cause nausea, abdominal cramps, fatigue, headaches, diarrhoea and kidney stones. High doses of vitamin C can also lead to dangerously high levels of iron, for example, as it interferes with the body’s ability to process or ‘metabolise’ other nutrients.

They increase your risk of developing cancer or do nothing at all

The above-mentioned study published in January 2008 also showed that taking beta-carotene supplements can increase a smoker’s risk of getting cancer and dying from it, while vitamin E supplements had no effect.

They reduce the health-promoting effects of exercise

Another research study published on 26 May 2009 found that taking antioxidant supplements could decrease the health-promoting effects of exercise (e.g. building muscle, improving your life expectancy, reducing your diabetes risk). Athletes and gym-goers who took antioxidant supplements to fight the extra free radicals produced by the body during exercise prevented their bodies from receiving the full health benefits of exercise.

They affect cancer treatments and medical tests

A breast cancer study published on 15 July 2009 found that 70% of women who took vitamin supplements during their cancer treatments, experienced a reduced effectiveness in their (e.g. radiation therapy, chemotherapy) from working properly. The reason is because the supplements helped protect cancer cells by getting rid of the cancer-fighting free radicals produced by the treatments.

Consuming large amounts of vitamin C can also interfere with medical tests, e.g. when taking a test for diabetes, it could give a false result.

They increase your risk of early death or, again, do nothing at all

A review published on 14 March 2012, which included 78 randomised clinical trials that looked at 200,000 healthy people and 81,000 people who had different types of diseases, revealed that there was no evidence to prove the benefits of taking antioxidant supplements. Moreover, those who took beta-carotene and possibly vitamins A and E had an increased risk of early death.

More recent research, published on 10 July 2014, also showed that taking antioxidant supplements can shorten one’s life expectancy. Lung cancer patients who took supplements in addition to taking natural sources of antioxidants (e.g. food) ended up dying sooner instead of living longer. This is because when antioxidants are added to foods, healthy parts of whole foods go missing (e.g. fibre). This means that antioxidant supplements won’t be as successful in preventing diseases as a diet rich in natural antioxidants.

Are antioxidant supplements unnecessary?

Some people need supplements

You should only take antioxidant supplements if recommended by your doctor or health practitioner, which is especially the case if you have an inadequate diet. If you do need them, take multivitamin supplements at the recommended dietary intake, instead of taking single vitamin supplements and in high doses.

People who can benefit from taking supplements include pregnant and breastfeeding women, those who consume lots of alcohol, drug users, those on long-term restrictive weight loss diets, the elderly, and those with malabsorption problems (e.g. diarrhoea, pancreatitis, coeliac disease and cystic fibrosis).

For women planning to get pregnant, folic acid supplements can reduce the risk of their baby getting neural tube defects (e.g. spina bifida). For people on a vegan diet, particularly if they’re pregnant, they may benefit from taking vitamin B12 supplements.

Free radicals can be good for you

Free radicals can be beneficial to you and your body. For example, when you exercise you produce extra free radicals that are essential to the health benefits that exercise brings, meaning that these extra free radicals trigger your cells to make your own antioxidants which give you the benefits of exercise. So taking antioxidant supplements during exercise is unnecessary.

Free radicals can also be helpful in an oxidative burst – this is when phagocytes (special immune cells) release free radicals to get rid of bacteria and viruses.

Antioxidants can be taken from natural, healthier sources

Antioxidants can be taken from a variety of natural foods and drinks, which is a healthier option. This includes: 

  • Vitamin A from foods rich in beta-carotene (e.g. carrot, beetroot, sweet potato, spinach).
  • Vitamin C from citrus fruits, berries, raw cabbage and broccoli.
  • Vitamin E from wholegrains, nuts, fish oil, and green leafy veggies.
  • Beta-carotene and its related carotenoids (e.g. lycopene, lutein) from fruits and veggies of a red, yellow, and orange colour.
  • Selenium and manganese minerals from seafood, lean meat, nuts, and whole grains.
  • Flavonoids from tea, coffee, and berries.
  • Resveratrol from red wine and dark grapes.
  • Phytoestrogens from peanuts and soybeans.

Natural antioxidants lower your cancer and mortality risk more than supplements

Around 200 studies have shown that people who ate fruits and vegetables were less likely to get cancer. And according to the above-mentioned study published on 10 July 2014, lung cancer patients who were given a diet rich in natural antioxidants were more likely to live longer.

Overall, a varied and balanced diet that includes antioxidant-rich foods and drinks (e.g. fruits, veggies, whole grains, cereals, tea, and coffee) is still considered healthier than taking antioxidant supplements. And despite the fact that free radicals can damage healthy cells, they’re also beneficial to your body, so suppressing their production with supplements isn’t necessarily a good thing to do. In the end, taking artificial antioxidant supplements may do you and your body more harm than good.

Suggested Articles

  • Dietitian help to lose weight

    How a dietitian can help you lose weight

    Nicole Dynan, Accredited Practising Dietitian, shares how a dietitian can play a pivotal role in helping people achieve real and lasting weight loss.
    • Fitness
    10 July 2019
  • AGM

    Advance Notice of Annual General Meeting and Director Nominations

    CBHS wishes to advise its members that the Annual General Meeting this year will be held on Thursday 7 November 2019 at the CBHS registered office, Level 5, 79 George Street, Parramatta, NSW 2150.
    9 July 2019
  • House Plants

    Indoor houseplants: On-trend and beneficial to your health

    The indoor plant is back and bigger than ever. And it has a lot more to offer than Instagram eye-candy and home beautification. In fact, they could be benefiting your health right now.
    • Wellbeing
    13 June 2019
  • Healthy Food

    How to food swap to fuel the workaholic you

    Food that fuels can make all the difference to your workday energy levels. We share our easy and work-friendly breakfast, lunch and snack ideas for success.
    • Nutrition
    13 June 2019