Are supplements the same as food?
Supplements are often marketed as an easy alternative to food. For example, for various reasons, many don’t eat fish but may take a fish oil capsule. There is a misconception that taking fish oil is “equal to” eating fish and that taking fish oil will provide the missing health benefits of not having fish in their diet. However, there are more beneficial nutrients in fish that that just omega 3. Another example is magnesium. Studies have shown that people with a high dietary intake of magnesium have a lower risk of heart disease and stroke. However, studies on magnesium supplements for heart health have had inconsistent results. Magnesium rich foods are also high in potassium and fibre, so it’s hard to separate out the effect of just one nutrient. So, again, just like fish is more than just omega 3, foods rich in magnesium, cannot be substituted with a magnesium supplement.
What about absorption?
Many are unaware that the body is usually better at absorbing nutrients from food, especially as part of a meal, than from supplements. A supplement may contain more of a vitamin or mineral than a food containing the same vitamin or mineral, but that’s not to say we’ll absorb it all. For example, we absorb about 30% of the calcium in a 500mg calcium supplement. If we then double our intake of calcium supplementation from 500 mg to 1,000 mg, we don’t double the amount we absorb. In fact, we may absorb only 20%. It is therefore best to spread our intake of high calcium foods throughout the day rather than get one or two large doses of calcium from a supplement.
They’re natural, right?
As supplement use continues to increase, so too are the side effects associated with their use. Supplements are viewed as ‘natural’. They may also have other ingredients (from plant +/- herbal products which sound harmless) but may cause harmful reactions in some.
“The more the better”?
Supplements are often viewed as safe and some hold the belief that “the more the better”. However, when taken in excess, can be toxic. There was a resent report of a man being prescribed 8 drops of 500 IU Vitamin D by his naturopath (a total daily dose of 4,000IU). He instead purchased a brand containing 1,000IU per drop, took 8 – 12 drops per day and was therefore taking a daily dose of 8,000 – 12,000 IU. After treatment by his doctors, his blood test results returned to normal however, he was left with chronic kidney disease.
“Just in case”!
Many take supplements “just in case” their diet is short in nutrients. However, most people don’t require a supplement since a balanced diet provides all the nutrients we need for good health. If we are already getting enough, from foods and fortified products, we could potentially be overdosing and creating harm.
Are some more likely to need supplements?
Yes. In particular,
- Women planning a pregnancy or who are pregnant
- Adults with osteoporosis who are not meeting their requirements for nutrients for bone health
- People with measured vitamin B12 deficiency
- People who are prone to malabsorption (eg. digestive conditions)
- People who have had bariatric surgery
- People with compromised food intake
If you are anxious about not meeting your requirement of nutrients or need further advice on if, and how much supplementation you need, please speak with your doctor or an Accredited Practicing Dietitian.