How to choose dietary supplements
Written by Dr. Daniela Steyn
Co-authored by Medical Writer Gerda Venter

Your best friend with luscious thick hair swears by her biotin and collagen supplements, and now you are considering supplements hoping to grow thicker, fuller hair. But how do you decide which one is right for you and if you should even be taking supplements?
When it comes to supplements, there are seemingly endless choices available on the market. With all the options out there, it can be challenging to know which one is right for you. I have a shelf full of supplements that I don't use. Patients often ask my advice about supplements. I created this guide to help you understand what to look for when choosing a supplement and how to find the one best suited to your needs. Once you have decided on a supplement, still talk to your doctor before you purchase it.
What are supplements?
Supplements are simply substances taken to supplement your diet. The broader term "supplement" typically includes vitamins, minerals, herbs, and other natural remedies.
Supplements are often used to improve overall health, boost immune system function, or address a specific medical condition. Popular supplement purchases usually include multivitamins, vitamin D, and fish oil capsules. Supplements are becoming increasingly popular among consumers who want to optimize their health and wellness goals.
When I was a medical student, we were taught that, in most cases, people don't need supplements. Then tongue in cheek, someone would add: "the only thing supplements do, is make expensive pee." Meaning that we urinate most of our water-soluble supplements out. Unfortunately, times have changed significantly since then.
The good, the bad and the ugly
Many people do need supplements. The supplement industry is rapidly growing as more people become aware of the benefits that these products can bring to their lives. Supplements provide additional nutrients such as vitamins, minerals, omega-3 fatty acids, probiotics and herbal extracts, which are not present in our diets. Unfortunately, even when you eat a perfectly healthy organic diet, our soil is depleted of many essential nutrients. You might get fewer nutrients from your food than you did twenty years ago.
When I admit patients to the hospital, I always do blood work for certain essential minerals: Calcium, Magnesium, Phosphate, Sodium, Zinc and Vitamin D. I am surprised at how often people are deficient in these. These essential compounds help support healthy brain function, skin health, regulation of hormones and digestion.
We often advise taking additional supplements for people with known medical conditions such as kidney disease, osteoporosis, or restrictive diets. Athletes generally find that supplementing with certain ingredients may improve overall athletic performance by providing more energy and endurance for intense exercise sessions.
Despite their importance and popularity, supplements should be used with caution as they can interact with other medications, cause adverse reactions and lead to nutrient imbalances if you take too much. Taking too much of any supplement could be harmful. Fat-soluble vitamins, vitamins A, D, E & K, get stored in fat, so if you take too much, you won't urinate the excess out; it can build up and cause toxicity. It is best to always consult with a healthcare provider before starting any supplement use.
Do you need to supplement?

The good news is that most people do not need to take supplements. In Canada, our guideline is that everyone needs a