Vitamin D in Canada: What to Know First

I'm a licensed esthetician, not a doctor. Vitamin D is a vitamin you can take too much of, and it can interact with some medications. Before you start, change or stop any vitamin D, talk to your doctor or pharmacist. This is knowledge only. I'm not paid by any brand and have nothing to sell.

Most Canadian adults are advised to get 600 IU a day (800 IU if you're over 70), and to stay under 4,000 IU a day unless a doctor tells you otherwise. Health Canada also suggests adults over 50 take a 400 IU supplement. Vitamin D supports bones and teeth. Big trials have not shown that extra vitamin D prevents cancer or heart disease in healthy people. Your doctor or pharmacist is the right person to tell you what you need.

Why Canadians talk about vitamin D so much

• The "vitamin D winter." Most of Canada sits so far north that, from about October to March, the sun is too low for your skin to make much vitamin D (University of Calgary School of Public Policy, 2015).
• Low levels are more common in winter. Statistics Canada found the share of Canadians with very low vitamin D more than doubles from November to March (Statistics Canada, 2023).
• Few foods have it naturally. Fatty fish and egg yolks do. Fortified foods like milk are the main dietary source in Canada (Osteoporosis Canada, 2026).

How much? The Health Canada numbers

Sources: HealthLinkBC, BC Guidelines: Vitamin D Testing, Osteoporosis Canada.

The upper limit is a safety ceiling, not a goal. Some people, for example with osteoporosis or certain conditions, are told to take more, but that is a decision for their doctor (HealthLinkBC).

What vitamin D can and can't do

One note for fairness: the VITAL researchers saw a possible drop in cancer deaths, and say people taking vitamin D on their doctor's advice shouldn't stop (VITAL study; U.S. National Cancer Institute; VITAL fracture study).

Vitamin D and your skin: the honest version

• Pills for skin? The American Academy of Dermatology's eczema guideline found inconsistent to no evidence for vitamin D supplements. Some smaller reviews show modest improvements, but researchers say cause and effect is still unproven (U.S. NCCIH; Int. J. Mol. Sci., 2025).
• Sun for vitamin D? BC's medical guideline does not recommend sun exposure to raise vitamin D, because of skin cancer risk. Tanning beds are not recommended either, and window glass blocks the rays that make vitamin D (BC Guidelines).
• So keep your SPF. Food, and a supplement if your doctor agrees, are the safer routes.

Do I need a blood test?

Ask your doctor. In BC, routine vitamin D testing is not recommended for most healthy adults, and the test is usually only covered by MSP for people under 19 or when a specialist orders it. Your doctor will know if your health, medications or history make a test worth it (BC Guidelines: Vitamin D Testing).

Read the label: a 6-point checklist

1. IU or mcg? Labels may use either. 1 mcg = 40 IU, so 25 mcg = 1,000 IU.
2. Dose per serving. Check how many drops, tablets or softgels make one serving.
3. Add up everything. Multivitamins, calcium + D combos, omega-3 oils with D3 and fortified foods all count toward your daily total.
4. Look for an NPN. An 8-digit Natural Product Number means Health Canada has licensed it. You can check it in the Licensed Natural Health Products Database (HealthLinkBC).
5. D3 or D2? Both are forms of vitamin D. Osteoporosis Canada names D3 (cholecalciferol) as its preferred form.
6. Bring the bottle. Show it to your pharmacist. They can check it against your medications in minutes.

A product can have a real NPN and still be promoted beyond what Health Canada approved. Health Canada says promotional claims must stay within the product's licence, and warns about advertisers who exaggerate effectiveness or make claims the licence doesn't support. That can happen in company ads, on websites, or in a seller's social posts (Health Canada).

How to check in 2 minutes: type the NPN into Health Canada's LNHPD and read the Recommended use or purpose. If what you're being told goes further than that line, ask why. Health Canada also says no health product should be called "safe" or "side-effect free."

Medications to ask about

Vitamin D can interact with some medicines. Examples include water pills called thiazide diuretics (risk of high calcium), corticosteroids such as prednisone, some seizure medications, and the weight-loss drug orlistat. This list is not complete. Ask your pharmacist before you combine (NIH Office of Dietary Supplements summary, via Examine).

Ask how it's sold

Some supplements are sold through multi-level marketing (MLM), also called network marketing or direct sales. In Canada, MLM is a legal business model when it follows the Competition Act. In an MLM, the person recommending the product is usually a sales participant who earns from your purchase, and who may also be paid when people they bring in buy (Competition Bureau Canada; Canadian Consumer Handbook).

That doesn't make a product good or bad. It simply means it's worth asking a few calm questions. These are the same questions I'd want you to ask about anything anyone recommends, including me:

• Do you earn money if I buy this, or if I join?
• Does it have an NPN, and do the claims match what Health Canada approved?
• Is there a monthly auto-ship or a minimum order?
• Are you comfortable with me checking with my doctor or pharmacist first?

A good seller will welcome these questions. In the U.S., the Federal Trade Commission has reminded MLM companies that they are responsible for the health claims their sellers make (FTC, 2020).

Claims to question

If you see these, pause and ask your doctor or pharmacist:

1. "Everyone is deficient, so take a high dose."
2. "10,000 IU a day is safe for everyone."
3. "Prevents cancer" or "protects your heart."
4. "Cures colds and flu" or "boosts immunity" as a cure.
5. "Clears acne, eczema or psoriasis."
6. "Replaces sunscreen" or "get your D from tanning."
7. "Natural, so you can't overdo it." Vitamin D is fat-soluble and is stored in the body.
8. "Doctor-formulated" used as proof. Ask what the evidence is, not who designed it.
9. "Detox" or "balance your hormones" with no NPN or approved claim.
10. "No need to talk to your doctor." That one is always a red flag.

In Canada, approved vitamin D claims are along the lines of bones and teeth, calcium and phosphorus absorption, and normal immune function (Health Canada licensed claims, via IFT).

Vitamin D questions I hear in the studio

Your next step

Write down what you take now, including multivitamins and oils, and bring the list to your doctor or pharmacist. If we're chatting during your treatment, I'm happy to share what I know, but they are the ones who should guide your dose.

An informed client is an educated one.

Disclosure: This is Part 2 of Inner Beauty, Informed, a knowledge-only series. I'm a licensed esthetician, not a doctor, dietitian or pharmacist. I'm not paid by any brand, and I don't sell supplements. This applies to every product, including any I might use myself.

Related: Part 1: Do Collagen Supplements Work? · All articles

General education only, not a substitute for advice from your physician or pharmacist.