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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 Vitamin D supplement daily. If you live closer to the equator and don't cover yourself with UV sunscreen and UV shirts daily, you won't need vitamin D. If you eat a varied and balanced diet, and the soil of your area is not depleted from minerals, you likely get all the nutrients you need from food. However, there are some exceptions. Some people cannot absorb nutrients as well from their food; we often see this in patients with inflammatory bowel disease or after chemotherapy. I do bloodwork more often to supplement deficiencies for these patients.

There are certain groups of people whom we supplement without testing. For example, pregnant women and young children may need certain nutrients, such as iron and folic acid supplements.

People who don't eat meat or animal products may also need supplements to get enough Vitamin B12. Common signs and symptoms I see in patients with Vitamin B12 deficiencies are:

  • Visual or skin changes

  • Anemia

  • Bone changes

  • Neurological issues

  • Blood clotting issues

  • Hair loss or brittle hair

  • Brittle nails

  • Fatigue

Talk to your doctor or a registered dietitian if you have any of these symptoms. Testing can help identify potential deficiencies and determine why you're low on a particular nutrient, whether because of diet or an underlying health condition.

The best way to get the vitamins and minerals you need is by eating a wide variety of foods, including vegetables, fruit, whole grains, milk and alternatives, and protein foods such as legumes, nuts and seeds, fish, and lean meats. A supplement can't make up for an unbalanced diet. However, some people may need a supplement to help them meet their needs. They include:

  • People who eat a calorie-restricted diet that does not provide enough vitamins and minerals.

  • Women who might get pregnant, are pregnant or are breastfeeding to be sure they are getting enough folic acid.

  • People who are sick, injured or recovering from surgery.

  • People with inflammatory bowel disease, kidney disease, a disrupted microbiome (bacteria in your gut that helps you absorb food)

  • People with limited sun exposure, as UV light in our skin helps to change cholecalciferol into Vitamin D.

  • People who can't or don't eat a variety of foods, such as people who have food allergies or eat a vegetarian diet.

Some supplements are only used under certain conditions. These include:

  • Melatonin to help reset your biological clock when you have jet lag,

  • Lysine when you have a cold sore,

  • Magnesium Bisglycinate to help you relax stiff muscles,

  • Magnesium oxide when you are constipated,

  • Vitamin C and Zinc when you have a cold.

  • Other supplements we take every day; for example, a patient who has to take a statin for high cholesterol will take Coenzyme Q10 to help protect their muscles.

  • Athletes might take salt tablets and glutamine before long workouts but not at other times.

What to look for when choosing a supplement?

Ultimately, there are three things you want from dietary supplements:

  1. That the products are safe

  2. That the products work

  3. That the products are worth the cost

The Canadian Natural Health Products Regulations require manufacturers and business owners to obtain a product license before making or selling a natural health product in Canada. Individuals must submit a product license application to the Natural and Non-Prescription Health Products Directorate (NNHPD) to get a product license. The application must include sufficient data to allow the NNHPD to assess the natural health product's safety, quality and efficacy when used under its recommended conditions.

The Food and Drug Administration (FDA) is responsible for ensuring supplement safety and effectiveness and establishing standards for supplement manufacturing, labelling, and advertising in the United States of America. Supplements must be labelled with specific information about their ingredients, dosage amounts, directions for use, and potential health risks or benefits associated with taking them.

Before a supplement can be sold in the United States, it must meet the requirements of Good Manufacturing Practices (GMP) set out by the FDA. GMP requires supplement manufacturers to properly manufacture, package and label products and test product purity and strength. To ensure that supplement companies follow these regulations, the FDA conducts inspections of manufacturing sites and product testing. This helps guarantee that all supplement products meet strict safety standards and are appropriately labelled for consumer protection.

Additionally, supplement manufacturers must register with the FDA before selling any dietary supplements in the United States. By registering their products with the FDA, supplement companies show that they take product safety seriously and are committed to providing consumers with safe and effective supplements. Taking the time to research supplement brands, ingredients, and reviews can help ensure that you get a supplement that meets your needs.

Unfortunately, due to a lack of oversight and enforcement, the FDA regulations need to do more to ensure authenticity, purity, safety, and efficacy. So, how can you be sure the products you want to purchase are safe, effective, and authentic? Here are a few tips:

1. Review the supplement label

Consider the following:

  • Does the product contain your desired ingredients and dosages?

  • Does the product design and dosage make sense?

  • Does the product fully disclose ingredients?

  • Does the label contain any "too good to be true" claims? Does it claim to treat, cure, or prevent a disease?

  • Does the label contain all the information required? Including the supplement's name, supplier name and contact information, ingredients and serving size, allergens, warnings, and other considerations for use.

  • Does it show allergen statements? By law, manufacturers must disclose the presence of the eight most common food allergens: Crustacean Shellfish, fish, egg, dairy, wheat, tree nuts, peanuts, and soybeans.

  • Is the product expired? Only buy supplements that have expired or that will expire before you can finish the bottle.

2. Evaluate the brand

When choosing a supplement, looking for reputable manufacturers who use high-quality ingredients in their products is essential. Here are a few tips:

- Look for supplements that an independent third party has tested. Some third-party identifications to look for include:

  • NSF certification: This type of certification uses strict standards to evaluate products and involves regular onsite inspections.

  • USP Verified Mark: This mark verifies that ingredients, potency, and amounts are accurate and free of harmful contaminants. It also verifies that the products are made according to FDA's current good manufacturing practices (CGMPs), confirming that the products were produced in a sanitary and controlled way.

  • Banned Substances Control Group (BSCG) Certified Quality and GMP: BSCG Certified Quality verifies ingredients and checks for dangerous substances. BSCG Certified GMP audits manufacturers to make sure they comply with CGMPs.

  • USDA certified organic: Products with this certification undergo rigorous review to ensure their quality and integrity meet USDA organic regulations.

  • Certifications: Certifications can indicate information about the supplement, including whether it's vegan, USDA organic, gluten-free, kosher, and more.

- If the supplement has a Natural Product Number (NPN) or a Homeopathic Medicine Number (DIN-HM), the supplement meets Health Canada's safety, quality, and health claims standards.

- Has the brand ever been investigated or recalled?

Vitamins and supplements may provide benefits that can help with various health concerns. Before you start taking a vitamin or supplement, talk with your doctor. Your doctor will help you determine whether you have a deficiency and provide advice on supplementing safely. If your healthcare provider advises you to supplement your diet, taking the time to research supplement brands, ingredients, and reviews can help ensure that you are getting a supplement that meets your needs. Are you using supplements? Let us know which one is your favorite in the comments section!

Reference list

2. Choosing a Vitamin and Mineral Supplement | HealthLink BC.

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