Vitamin D is one of the most common supplements in North America, especially in winter. A few simple choices make a real difference to how well it works for you.
D3 or D2: which is better?
There are two main forms. Vitamin D2 (ergocalciferol) comes from plant and fungal sources. Vitamin D3 (cholecalciferol) is the form your skin makes from sunlight. Studies comparing the two have generally found that D3 raises and maintains blood levels of vitamin D more effectively than D2, which is why D3 is the form most often recommended.
Take it with a meal
Vitamin D is fat-soluble, so it is absorbed best with food that contains some fat. Taking it with a meal, such as breakfast with eggs or yogurt, or dinner with fish, olive oil or avocado, helps your body use more of it than taking it on an empty stomach.
Is there a best time of day?
The time matters less than consistency. Choose the meal you are most reliable with and link it to a daily habit. Some people find taking vitamin D late at night affects their sleep; if so, take it earlier in the day.
Daily is better than occasional big doses
Research on vitamin D and immune health suggests steady daily or weekly dosing works better than very large doses given every month or few months. A small daily capsule is the simplest way to stay consistent. Read more in vitamin D and your immune system.
How much vitamin D do you need?
US and Canadian guidelines recommend 600 IU a day for most adults up to 70 and 800 IU over 70, assuming minimal sun. The general upper limit for adults is 4,000 IU a day. Higher amounts, such as 5,000 IU, are sometimes used to raise low levels, but should be taken with guidance from a healthcare provider, ideally based on a blood test. Your provider can recheck your level after about three months to see where you are.
Tips for getting the most from vitamin D
- Pair it with calcium-rich foods, such as dairy, fortified plant drinks, canned salmon with bones or leafy greens, since vitamin D helps your body absorb calcium.
- Get your level tested before taking higher doses, and periodically afterwards.
- Count all sources. Add up vitamin D from multivitamins, calcium supplements and fortified foods so you don't take more than you intend.
- Store it well, in a cool, dry place out of direct sunlight.
Who should check with a doctor first?
- people with kidney disease, high calcium levels, sarcoidosis or a history of kidney stones;
- people taking certain medications, such as some diuretics, heart medications or steroids;
- anyone who is pregnant or breastfeeding.
Not sure if you are low? See vitamin D deficiency: signs, who's at risk and how much you need.
About CLE Vitamin D3 5,000 IU. One small capsule a day with a meal provides 5,000 IU of vitamin D3 (cholecalciferol), which helps maintain immune function and healthy bones and teeth. Each bottle holds 90 capsules, a 3-month supply. Because this is a higher-strength dose, check with your healthcare provider that it is right for you, ideally based on a blood test.
This article is general information, not medical advice. Talk to your doctor or pharmacist before taking vitamin D supplements, especially if you have kidney disease, high calcium levels or take medication.