Post No.: 0609
Without getting technical, antioxidants are compounds that can protect the body from unstable and potentially harmful molecules called free radicals, which can accumulate over time and promote oxidative stress and damage DNA and cells, which in turn increases the risk of diseases like cancers, heart disease and diabetes. Environmental factors such as ultraviolet rays and air pollutants produce free radicals, but natural bodily processes like when you exercise or digest food will too hence they’re an unavoidable part of living.
Some antioxidants are naturally produced in the body, like alpha lipoic acid and glutathione. They can also be obtained from foods, including those that contain vitamins like vitamins A, C and E, and minerals like copper, zinc and selenium. Produce that contain phytochemicals, like carotenoids, polyphenols or flavonoids, also contain antioxidants.
They can also be found in concentrated forms in dietary supplements. However, numerous studies appear to show that obtaining our antioxidants from dietary supplements is less preferable than from food sources. Randomised-controlled trials with real humans appear to show that antioxidant supplements don’t provide the protective effects we would expect them to offer, especially in otherwise non-malnourished groups. Also, high doses may even be harmful (some supplements contain >1,000% of the recommended daily amount of a vitamin!) Detrimental effects might include a higher risk of bladder cancer (ironically) after taking beta-carotene (a precursor to vitamin A) supplements, and birth defects after pregnant women take high-dose supplements of vitamin A. So unless instructed by your doctor to take particular supplements – get your antioxidants, vitamins and minerals, etc. from food sources.
It’s currently unknown whether it’s due to the synergistic effects of certain combinations of micronutrients (e.g. vitamins and minerals) and/or macronutrients (e.g. carbohydrates, proteins and fats) – as found in natural produce – that make them work more effectively in the body? Regardless, evidence on the benefits of multivitamin and mineral supplements to ward off disease or early death is currently mixed. It does however illustrate that in vitro (experiments in glass dishes) isn’t the same as in vivo (experiments in entire living organisms) when it comes to scientific research.
Whenever a study shows that antioxidants do something to cells in a test tube, beaker or Petri dish at a cellular level, and there’s even seemingly a clear mechanism to explain why free radicals are bad for us in the bloodstream – that’s merely demonstrating a surrogate outcome because what we’re really interested in is whether antioxidants improve people’s health in the real world and in real human bodies. Plus some ‘miracle compounds’ (such as resveratrol from red wine) require such enormous doses of it that it’s unrealistic or unhealthy for a real-world human being to take it, as opposed to a bunch of cells in a dish.
Consequently, despite the amount of research, antioxidants is one of those scientific areas that has been particularly confusing. Many phytochemicals – even those sourced from food sources – might not survive the digestive processes of a living body and therefore work as suggested? They might get transformed into some other chemical before being absorbed into the bloodstream, or be difficult to absorb or gets rapidly excreted from the body before they reach the desired cells (i.e. they have poor bioavailability)? Perhaps the advice will further refine as the scientific community learns more, especially regarding in vitro versus in vivo results.
For the foreseeable meantime, what isn’t in dispute, and is the overall practical takeaway, is to consume a wide variety of colours of fruits and vegetables as part of a well-balanced diet. We’ve heard this advice a million times before! Get your vitamins, minerals and other nutrients from food.
Some vitamins are more sensitive to heat during the pasteurisation process when canning so are better from fresh sources, like vitamin C. Conversely, tomatoes benefit from cooking when it comes to lycopene. But as a general rule – it’s okay whether they’re fresh, tinned, frozen, dried or fermented/pickled. However, whole fruits are preferred to juices or smoothies, and watch out for any added sugars or salt.
Even with these fresher or more natural sources of nutrients, you can still have too much so it’s about having enough each day rather than as much as you can stuff – excessive amounts of water-soluble vitamins like B and C will get excreted out whereas fat-soluble vitamins like A and E can build up to toxic levels because the excess is stored in the liver and fatty tissues. (Many pesticides accumulate particularly in the fatty tissues too.) It’s always about balance, never excess, to achieve optimum health. If something’s good, it doesn’t necessarily mean that having more of it is better. Antioxidant levels cannot be ‘boosted’ in the mid to long-term, thus smoothies or other products that claim to be able to ‘boost your antioxidant levels’ are misleading. In the long run, they could actually potentially decrease levels of antioxidants in the blood as the body adapts through the process of homeostasis to keep levels stable by flushing out any excess – ironically creating a more vulnerable state than if one didn’t consume lots of antioxidants at once. So I guess that getting more vitamins is like getting more money – you only really need so much, and the more you get, the more you’ll **** the rest of it away anyway(!) Meow!
Animal-based products like eggs and milk contain antioxidants too, but plant-based products like apples, oranges, broccoli, spinach, oats, kidney beans, pecans, walnuts, tea and coffee are particularly dense in them.
Fruits and vegetables high in carotenoids, such as carrots and peppers, can give your skin a subjectively healthier-looking glow – if this motivates you to eat more fruits and vegetables.
Curcumin from turmeric, flavonoids from sources like berries, and quercetin from sources like onions, have been found to help fight bowel cancer, increase concentration in school, and reduce inflammation, respectively, in initial studies. Cinnamon may help curb blood sugar levels by lowering insulin resistance too. Some products are marketed as containing flavonols (a class of flavonoids), which may have antioxidative effects or claim to help cognitive function or heart health. But the evidence concerning all of these is still inconclusive. Randomised-controlled trials, that have been independently repeated and verify the same results, are needed for more robust findings. Therefore I don’t agree with the media suddenly making a particular foodstuff or supplement appear ‘super healthy’, which leads to people consuming huge doses of it (until the next fad!), based on only early and inconclusive findings. But this is what tends to happen.
It’s the folly of being too easily lured towards the promise of ‘therapeutic, magic-bullet quick-fixes’ again and again. Even if something is truly that amazing, it’s never good in excessive amounts, whether it regards our health or wealth (because most fads are overpriced). It’s about having a bit of variety and balance every day.
Even if polyphenols can help prevent cancer and cardiovascular diseases, it’d be better to source them from tea, walnuts or apples, for instance, rather than red wine or chocolate, because then you’d get the pros without the cons from alcohol or refined sugar and fat consumption. They can be found in higher concentrations at and just below the skin of apples hence eating the whole fruit, including the skins if possible, is again better. Not all red wines or even dark chocolates are equal too, and it may be the case that even the best won’t contain enough of the desirable stuff to offer a beneficial effect unless consumed in such large quantities that you’ll have taken far too much of the undesirable stuff. (It’s like sea salt contains calcium, potassium and magnesium, which are good for us – but for the huge amount of sodium we’d also be consuming if we were to treat sea salt as a key source of those minerals, it’d be severely detrimental for our health.) Other, less profitable or headline-grabbing, products will contain the same nutrients, possibly more, and with more other good stuff too, without as much of the calories or expense. The marketing doesn’t have to lie to leave a consumer with incomplete information, but complete information is what’s needed in order to make a well-informed decision.
Most people get enough of most of their required micronutrients through their diet. Vegans usually manage it too. Those who voluntarily take vitamin supplements tend not to be those who most need to anyway because their conscientiousness to voluntarily and regularly take supplements normally gives them the conscientiousness to otherwise eat a sufficiently nutritious diet already. If you think you are deficient in any nutrient then please seek a blood test.
Vitamin C supplementation won’t prevent you from catching a common cold but may however reduce the severity and duration of one. The same may also be true of zinc supplementation if taken within the first 24 hours of catching one.
Vitamin D supplements, between the months of around October to March if you live in a country like the UK, are really the only recommended supplements to take without needing specific doctor’s advice. Humans can synthesise vitamin D from exposing their skin to sunlight (darker skin needs a longer time) but there’s insufficient sunlight during the darker months. 10μg per day is sufficient for most people over the age of 5.
Something to note though is that vitamin and mineral supplements aren’t regulated like pharmaceutical drugs are. This is because they’re not drugs. It does mean you cannot be sure that you’re getting exactly what the packaging claims – which is probably even more reason to preferably get your nutrients from food sources. Try to improve your diet before you use dietary supplements.
Of course, they might not always be wrong but the manufacturers, retailers and influencers who promote particular dietary supplements, extracts and processed products (when they fortify them with vitamins or minerals) aren’t going to be impartial about what they think. They profit from the hype of fighting cancer and slowing down our ageing! Even if you don’t have a specific health problem, they’ll want to sell you something as a prophylactic (a preventative measure). Behind the marketing and away from the front of the packaging, some of these products might even contain lots of sugar, which is known to cause health problems if consumed too much – so read the backs of packages for the ingredients and nutritional values lists. (If the free market for supplements would self-correct according to what the science says then that industry wouldn’t be anywhere as lucrative as it is!)
Diets high in refined carbohydrates (which includes sugar), animal proteins and fat can lead to oxidative stress. So can smoking and excessive alcohol consumption. So once more the take-home advice remains consistent with regards to avoiding obesity, smoking and drinking too much alcohol. When it comes to exercise – the positives of exercise still far outweigh the negatives.
…We should all continue to keep abreast with the latest meta-analyses but the current weight of evidence suggests that antioxidants are beneficial for us but we should rely on food sources rather than supplements, the body produces much of its own, and consuming high doses is generally potentially harmful. And although it’s still not fully understood yet, free radicals aren’t always bad at all times or in all places. They’re in healthy bodies for a potential reason – they kill undesirable bacteria and might increase insulin sensitivity during exercise.
Strengthen the capacity of your lungs, heart and fluffy joints, eat the right nutrients in the necessary amounts (no need to buy ‘in-fashion’ products or ‘superfoods’ unless you want to), and minimise toxins such as pollutants. There’s no need for deliberate detoxing though – see Post No.: 0184.
Meow. If taking supplements makes you feel good, you don’t experience any side-effects and you can afford it then I suppose it’s up to you whether you continue to do so. Whatever your stance on the subject, you can share it through the Twitter comment button below.