The Truth about Supplements

Have you heard that supplements will give you more energy and will drastically improve your health? Do these claims make you want to run to the store to buy the supplement with the hopes of ultimate health? Or do you wonder if it's really worth it?

Not all supplements actually help; and in fact, they could be harming you. Self-proclaimed “health experts” online might make convincing claims, but their advice could lack scientific backing, or they could be taking scientific information out of context.

For example: Magnesium supplements: like many other minerals, magnesium is good for you and has many benefits. However, that doesn’t mean you need to take a supplement. It is usually possible to get enough magnesium from nutrient-dense foods.

Despite how convincing they may sound, their conviction when making a claim does not have anything to do with whether or not their claims are accurate.

Why is food the best way to get nutrition?

The truth is - food is the best way to get nutrition, and it is possible for to get most (if not all) of the nutrients you need from food.

Nutrient-dense foods are the best way to get vitamins and minerals because it has a combination of other nutrients and healthful compounds including fibre, healthy fats, protein, carbohydrates, and phytonutrients.

Phytonutrients are responsible for the taste, aroma and colour of foods, and have many health benefits including antioxidant properties, anti-inflammatory properties and even anticancer properties.

Not only is it better to get as much of your nutrition as you can from food; taking too many supplements can cause more harm than good. Having too many vitamins and minerals can lead to toxicity.

Toxicity from consuming too many vitamins and minerals through supplements can cause a wide range of problems, such as suppressed immune system, stomach and intestinal problems such as abdominal pain, nausea, changes in bowel movements, and ulcers. It can also increase the severity of respiratory infections, impair kidney function and liver function, decrease bone density, and even increase risk of some types of cancer.

While having too little or too much of a nutrient can have detrimental effects, getting the right amount is important for both physical and mental health. Vitamins and minerals are important for hundreds of thousands of different processes in the body, including cancer prevention, immune function, bone health, brain health, collagen synthesis and skin repair, and insulin production and function.

Do I need to take supplements?

Whether or not you may benefit from supplements depends on many factors, including your diet, medical conditions, and what medications you take.

With a well-balanced, nutritious diet, it is possible to get most of the nutrients that you need through food sources. However, there may be certain vitamins or mineral supplements that some people need more of. For example, adults might need supplements in these cases:

Diet:

Infrequent consumption of specific foods:

If you avoid or limit certain foods, such as meat, fish, dairy, grains, vegetables, fruit, nuts, seeds, or legumes, your diet may be lacking in certain nutrients. If you are not able to consistently get enough nutrition, you may benefit from supplements.

For example, if you are not getting at least 2 servings per week of fatty fish, and aren't interested in having more, you may need an omega 3 supplement. The total amount of EPA and DHA (combined) that you get from this much fatty fish is about 1400–3500 mg per week (8).

Note: people who take blood thinners (such as warfarin) should talk to their doctor before taking omega 3 supplements. People who are pregnant also need to pay special attention to the source of their omega 3 supplement (see below).

Similarly, if you eat mostly plant-based foods, you could also be at risk of not getting certain vitamins and minerals. You can read more about these nutrients in the vegetarian/vegan section.

If you are unsure if you are getting enough of the nutrients you need from food, a dietitian can assess your diet and give you practical tips on how to meet your daily nutrition requirements. For general information about food sources of vitamins and minerals, check out this blog post on everything you need to know about vitamins and minerals.

Vegetarian and Vegan Diets:

Despite the fact that vegetarian and vegan diets have many health benefits and can be very nutritious, there are a few nutrients that are not absorbed as well by the body from plant- based foods (iron and zinc), which make it harder to meet nutrition requirements. In a vegan diet, other nutrients such as vitamin B12 and omega 3 are also harder to get enough of, unless consuming enough fortified foods and beverages.

Vegans and vegetarians may need fortified foods or supplements such as:

1) Multivitamin-mineral supplement for those who need more iron, vitamin B12, zinc (and calcium + vitamin D too, if needed). If you are not getting enough of the food sources of these nutrients, you may benefit from a supplements in order to meet your nutrition needs. Some fortified food and beverages can also be a good way to get more of these nutrients, which could be an alternative to supplements if preferred.

Multivitamin-mineral supplements are a good way to get a smaller amount of all the vitamins and minerals, rather than taking high doses of the nutrients separately. If you have a deficiency, however, you may need a higher dose of that nutrient, and can get specific supplementation recommendations from your doctor.

2) Omega 3 supplement (EPA and DHA, more specifically) for those who do not eat seafood. EPA and DHA is the type of omega that is found in fish and seafood, but also found in small amounts in seaweed. This type of omega 3 is different than ALA, which is a different type of omega 3 that is found in plants such as flaxseeds, flax oil, hemp seeds, soy, walnuts, walnut oils, and canola and soybean oils. Some of the ALA can be converted to EPA + DHA in the body, but in very low and insignificant amounts (2).

For reference, it would take at least 2 servings per week of fatty fish to get the ideal amount of EPA and DHA omega 3 from food sources. So, if you are not getting this much from food sources, you would likely benefit from an omega 3 supplement.

Gluten-free diets:

If you avoid wheat products, you may not be getting as much iron and B vitamins from refined flours.

Whole grains are a good source of many nutrients, but when they are refined, they are stripped of some important nutrients including iron and B vitamins. Fortunately, there is a mandatory fortification of white flour (wheat-based) in Canada, and nutrients including iron and B vitamins have to be added (1). Gluten-free flours, however, do not have mandatory fortification, and so many of these flours end up having lower amounts of vitamins and minerals.

If you are following a gluten-free diet and rely on flours for nutrition (such as pasta and bread), you may need to pay extra attention to getting enough iron, B vitamins, and folate.

Vitamin D:

It can be difficult to get enough vitamin D from food sources alone. The Recommended Daily Allowance (RDA) of vitamin D is 600 IU for people 19-70 years of age, and 800 IU for those who are 70 years and older.

 Since there is about 100-120 IU of vitamin D in a cup (250 mL) of milk, and about 100-400 IU in a serving of fish (depending on the type of fish), it would take either several servings of milk or milk alternatives per day, or a serving of fish plus milk or milk alternatives to get enough vitamin D. For those who are not consuming this much vitamin D from the diet, it can be helpful to get vitamin D in supplement form. Multivitamins often contain vitamin D and could also work as a way to get this extra vitamin D.

Keep in mind: the Tolerable Upper Intake Level (UL) for Vitamin D is 4000 IU per day (from both food and supplements) for adults. Having too much is also not good for the body! You most likely do not need a high dose vitamin D supplement, unless you have been diagnosed with a deficiency. In fact, 400 IU of vitamin D from supplements is usually enough (5)!

For more information about vitamin D from food sources and supplements, check out this blog post.

But what about the sun?

Our bodies have the ability to make vitamin D in our skin from the sun. However, not only is it hard to make vitamin D in the fall, winter, and spring months in Canada; direct sun exposure can be harmful, as it damages the DNA in your skin and can increase risk of skin cancer (4). Therefore, even if you do have the ability to get enough sun exposure in the summer months, it is actually recommended to cover up and wear sunscreen, which would decrease your production of vitamin D.

Aging:

There are two nutrients which people over the age of 50 years are typically unable to get sufficient quantities from food (in the natural form): vitamin D and vitamin B12. As people age, they do not absorb or produce enough of these nutrients, so a supplemental form of these nutrients help them to meet their needs.

1) Vitamin B12 in supplemental form, whether that is in fortified food or in supplements, is generally recommended for people over the age of 50 (3).

In the food form, vitamin B12 is bound to protein, which is harder to absorb if you are not producing enough stomach acid to break it down. As people age, they produce less stomach acid. The supplemental form of vitamin B12 is absorbed much better in these cases because it is not bound to protein. If you need a supplement, often the amount of vitamin B12 in a multivitamin is enough.

2) Vitamin D in supplemental form is generally recommended for people over the age of 50 (5).

Along with Vitamin D in foods such as fortified milk or milk alternatives, and fish, our body can also produce vitamin D in the skin from exposure to the sun. However, as people age, they can’t convert a chemical in their skin to vitamin D as well, so they usually need extra vitamin D. If you are taking a multivitamin, you can check how much vitamin D is in there- it might be enough. The multivitamins designed for people 50+ often have higher amounts of vitamin D and calcium.

Low vitamin or mineral status:

If you are at risk of deficiency, such as having history of low intakes of a nutrient or have a suspected decreased absorption of the nutrient, your doctor can order a blood test to see if you have a deficiency. If you have a deficiency, your doctor may recommend a high dose supplement (or even intramuscular injections, in some cases) to help treat your deficiency.

People who can get pregnant, are pregnant, or are breastfeeding: 

People who could get pregnant or are pregnant need to take supplements, because they have increased needs for vitamins and minerals. Even the first few days of pregnancy are important for neural tube development, which is why people who have the possibility of getting pregnant should generally take a multivitamin containing 400 mcg (0.4 mg) of folic acid daily (6). Some people need higher doses of folic acid. To read more, check out Health Canada's page here.

During pregnancy, people usually need a prenatal multivitamin-mineral to meet their nutrition requirements (which are formulated to have higher amounts of the nutrients that women need, such as iron and calcium, and contain important nutrients including folic acid, vitamin B12, and vitamin D).

Some pregnant people may need additional supplements, depending on their diet and medical conditions. For example, those who do not eat fish regularly often need an omega 3 supplement, and those who are at risk of nutrition deficiency of particular nutrients may need a higher dose supplement for those nutrients.

Note: When choosing an omega 3 supplement, pregnant individuals should avoid liver oils (such as cod liver oil) because these are high in vitamin A. High consumption of preformed vitamin A during pregnancy can cause birth defects.

Medical Conditions:

Inflammation of the digestive tract caused by infections or inflammatory bowel diseases such as celiac disease, Crohn's disease and ulcerative colitis, can decrease your absorption of nutrients. Having decreased absorption of nutrients often means you need to compensate by having higher intake of these nutrients. Therefore, supplements might be needed in these cases.

If part of your stomach or bowel (especially the small bowel, which is involved in a lot of vitamin and mineral absorption) have been removed, you may also have higher nutrient requirements. This is why, after bariatric surgery, many people need to take higher dose supplements for specific nutrients long-term.

If you have any of these conditions, it would be helpful to talk to your medical team about what supplements you should be taking.

Medications:

A range of medications can decrease absorption or utilization of nutrients.

For example, medications such gastric acid inhibitors (including proton pump inhibitors and H2 blockers), metformin and some anticonvulsants can decrease absorption and utilization of vitamin B12 (7). In these cases, people might need a supplement or fortified food that contains the supplemental form of vitamin B12 to ensure they are getting enough.

If you are taking medications, it can be helpful to check with your health care provider to find out if any of your medications affect your nutrient absorption.

Low Food Intake:

If you find it hard to meet your nutrition requirements through food sources, then you might need supplements or supplement drinks to ensure that you are still getting enough. This could apply for those with a low appetite, severe nausea or digestion problems, or for those with difficulty affording enough food.

In Summary,

If you are eating a balance of the food groups, and are eating lots of nutrient-dense foods, then it is possible to get most (if not all) of the vitamins and minerals from food.

If you aren't getting enough nutrition from food, a small dose of the nutrients in supplemental form is usually enough. You'd be surprised to see that you don't actually need a ton of those nutrients to get the benefits.

The only case where you might need a higher dose supplement is if you have a deficiency that is needing to be treated, or if you have a specific condition that is causing you to not absorb or utilize nutrients properly.

If you are wanting to get your diet assessed to see if you are getting enough nutrients, or if you have any medical conditions or medications that might affect your nutrient absorption, you can book a consultation with a dietitian.

So if you need a supplement, now what? Which one do you choose?

When looking for a supplement, you can compare the amount of nutrients in the supplement to the Recommended Daily Allowance (RDA) and the Tolerable Upper Intake Level (UL), to see if it a safe amount for the general healthy population. If you take multiple supplements, make sure to add up any repeated nutrients to get the total amount of the nutrient and ensure that it does not exceed UL. Keep in mind- you also get nutrients from food sources- so this will also count towards the RDA and UL too.

To ensure that the product is reliable, you can also check to see if the supplement is licensed in Canada. In Canada, products that have been assessed and approved by Health Canada to be safe, effective, and of high quality for their recommended use, will have an eight-digit NPN number or DIN-HM on the label.

It is also helpful to consider what other ingredients have been added to your supplement. If your supplement has a lot of herbs and extracts, for instance, this could affect your health. Herbs and extracts can be quite potent in a supplement form. These ingredients can be hard on the body in excess amounts, especially your liver which often has to process it, and can interact with medications. If the product has these ingredients, it would be helpful to check with your doctor and pharmacist to see if there is any risk to your health.

Before starting any supplements, it is a good idea to check with your doctor and pharmacist, to ensure that your supplements do not interact with your medications and are appropriate for your medical conditions.

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What is the RDA and UL?

Based on observations of the healthy general population in US and Canada, scientists were able to determine how much of each nutrient would meet most people's needs, based on sex and age. From these studies, they determined the Dietary Reference Intakes for vitamins and minerals, including the Recommended Daily Allowance (RDA) and the Tolerable Upper Intake Level (UL).

The Recommended Daily Allowance (RDA) is the average daily intake that would meet the needs for 97-98% of individuals in that age range and sex. The Tolerable Upper Intake Level (UL) is the highest average daily nutrient intake that would likely pose no risk of adverse health effects to people within the specified age range and sex. However, if someone consumes more than the UL, their potential risk for adverse effects increases.

Want more information? Check out the Health Canada DRIs and ULs for each vitamin and mineral here: https://www.canada.ca/en/health-canada/services/food-nutrition/healthy-eating/dietary-reference-intakes/tables.html

Disclaimer:

The content on this site is not meant to replace direct medical advice from your doctor or other qualified clinician.

The information on this page reviews nutrition considerations for adults only. Infants and children have different nutrition requirements.

People with medical conditions or altered blood levels of compounds may have different supplement requirements and contraindications, and should consult their doctor for their unique requirements.

References:

1. Mandatory Fortification of Foods in Canada

   Accessible at: https://inspection.canada.ca/en/food-labels/labelling/industry/nutrient-content/claims-reference-information#c1

   
   

2. Omega 3 Fact Sheet

   Accessible at: https://ods.od.nih.gov/factsheets/Omega3FattyAcids-Consumer/

   
   

3. Daily Reference Intake Table for Vitamin B12, with vitamin B12 supplement recommendations for those over 50 years of age listed at the bottom of the page.

   Accessible at: https://www.canada.ca/en/health-canada/services/food-nutrition/healthy-eating/dietary-reference-intakes/tables/reference-values-vitamins.html#tbl3

   
   

4. Health Canada Page on Sun Safety

   Accessible from: https://www.canada.ca/en/public-health/services/sun-safety/skin-cancer.html

   
   

5. Health Canada Page with Vitamin D Information

   Accessible at: https://www.canada.ca/en/health-canada/services/nutrients/vitamin-d.html 

   
   

6. Health Canada Page with Folic acid Information Before and During Pregnancy

   Accessible at: https://www.canada.ca/en/public-health/services/pregnancy/folic-acid.html

   
   

7. BC Guidelines Page on Vitamin B12 and Folate Deficiency

   Accessible at: https://www2.gov.bc.ca/gov/content/health/practitioner-professional-resources/bc-guidelines/vitamin-b12

   
   

8. Omega 3 Resource from Alberta Health Services

   Accessible at: https://www.albertahealthservices.ca/assets/info/nutrition/if-nfs-omega-3-fats.pdf