Downsides to Supplements
Supplements allow nutrients to be taken in concentrated forms, far higher than you might find naturally occuring in whole foods. This can have harmful effects on health. For Example, overconsumption of Vitamin A can lead to a toxic build up in the liver (2). It has also been found that green tea extract, not in drinking tea form but in powdered or supplement form, can cause toxification and liver damage (3).
Negative Interactions With Medications:
You should always check with a medical professional if you are taking medication and supplements at the same time. There are lots of possible negative interactions. For example, 5 HTP (a sleep supplement) cannot be taken with antidepressants.
With Other Nutrients:
Some nutrients compete for the same pathway to get into the bloodstream. For example, if you supplement with too much Zinc, (which is not hard as the recommended dose is only 8 mg per day) you may reduce your ability to absorb copper.
With Lifestyle Factors:
In some cases supplementation has actually been found to have negative effects on long term health. For example, beta-carotene supplementation has been found to significantly increase the risk of lung cancer in smokers (2,4). Which is concerning as beta-carotene is commonly found in multivitamins.
No Regulation Around Effective Dose:
There is no regulation on whether the product is actually useful or effective in terms of what the supplement is or how much of the ingredient it contains (5). For example, turmeric research shows we need at least 500mg of curcumin (the active compound) to reduce inflammation, however I have seen turmeric supplements with 7mg per serve! You are effectively paying for a light dusting of an ingredient.
Supplements are often expensive. Since we have to eat regardless of buying supplements anyway this is on top of our grocery bill. That money may be better spent contributing towards good quality nutrient dense foods.
The level of nutrient absorption (bioavailability) from supplements is not well regulated. There is a lack of relevant studies supporting bioavailability of supplements in humans as a lot of the research is carried out in laboratory test tubes and in animals (6). For example, black pepper and fat is required for effective absorption of turmeric compounds but not always found in the supplements.
- Easier to overdose on supplements
- Supplements can negatively interact with medications, other nutrients or lifestyle factors
- No guarantee you are taking an effective product or dose.
- Supplements can be expensive
- No guarantee it is being absorbed