jamieson multivitamins

How To Get the Most Out of Your Multivitamin

Aug 31, 2022

Do you take a multivitamin every day? Almost one-third of Canadians take a daily multi to ensure they’re not missing out on any essential vitamins, minerals and co-factors.1 Another 16% percent of people choose to occasionally add a multivitamin to their daily regime when they feel run down or sick.1

Regardless, if you’re a regular consumer or occasional, I often find people are not getting the most out of their daily multi. There are several factors that can influence how well, or not so well, your body absorbs and utilizes your daily multivitamin. Let’s explore.

1. What time of day is best? 

Most people take their multivitamins first thing in the morning with breakfast. This is a very practical strategy because compliance is generally highest first thing in the morning (i.e., you’re less likely to forget compared to the end of a long, busy day).

However, certain nutrients have a diurnal variation, meaning absorption is better or worse at specific times of the day. Iron is a great example.

If you’re struggling with low or inadequate iron status, morning may not be the best time to take your multivitamin with iron. Why? New research shows iron absorption is higher in the afternoon compared to the morning due to the activity of an enzyme called hepcidin, which is higher in the morning and hampers iron uptake.2

Pro Tip - If your iron is low, consider taking your multi at lunch or dinner (or adding an iron-specific supplement at that time). Iron is key for building red blood cells and supporting energy. If iron isn’t a concern, the morning is still a great time to take your daily multivitamin.

2. Should I take A Multi If I Have A GI Condition?

If you’re struggling with a chronic gastro-intestinal (GI) condition like celiac disease, ulcerative colitis (UC), or cystic fibrosis, then you’ll likely be experiencing compromised or inadequate absorption of key minerals. In this context, a multivitamin can be very impactful to ensure you’re meeting your micronutrition needs.

If your gut challenges are more related to gas, bloating or sluggish bowels, this shouldn’t adversely affect the uptake of your daily multi (although healthy gut microbiome does help produce vitamin K, b-vitamins, key shortshort-chain, and the like).6

An often-overlooked group are those who’ve had gastric bypass surgery for weight loss. The removal of a section of the stomach and small intestine compromises absorption of certain micronutrients, like vitamin B12, calcium and vitamin D, and iron, so adding a multivitamin is a commonly-advised strategy by doctors.

Pro Tip – If you have a GI condition or have had gastric bypass surgery, consider adding a multivitamin to your daily regime to make sure you’re getting all your vitamins and minerals.

3. What About Interactions with Medications?

High blood pressure, defined as greater than 140/90 mmHg in the last month, affects approximately 1 in 4 Canadians.7 One of the most commonly prescribed drugs for elevated blood pressure (BP) is called diuretics, which help to lower BP but can also lead to lower levels of magnesium, potassium and calcium.

Heartburn is another condition for which medications called proton pump inhibitors are commonly prescribed. This class of drugs helps to reduce stomach acid levels to relieve pain, but they also compromise the absorption of vitamin B12, calcium and magnesium.

Pro Tip - Taking your multivitamin away from the time you take your medication is important to avoid any drug-nutrient interactions (and always consult your doctor before adding any supplements to your regime).

4. Women’s Health & Pregnancy

Multivitamin support in pregnancy is a must as pregnant women need to ensure they’re getting sufficient folate to lower the risk of spina bifida or anencephaly in the fetus. However, many women don’t realize folate is most effective in the first few weeks pre-pregnancy (a time when a woman may not be aware she’s pregnant), the primary reason why government recommendations are for all women of childbearing age to consume 400mg folic acid daily. Other key nutrients in pregnancy include iron, calcium, vitamin D and omega-3 DHA.8

5. As You Age, Should You Take a Multi?

As you reach your late 60s and beyond, subtle changes in your food choices make it more likely to be experiencing vitamin and mineral insufficiency or deficiency. For example, poorer food choices (i.e., more ready-made meals and a lack of motivation to cook fresh food), difficulty chewing (and swallowing) and interactions with medications (not to mention social factors like loneliness) can all depress appetite. The National Academy of Medicine recommends people over 50 eat foods fortified with B12 (or consume adequate animal protein) and multivitamins become increasingly important to ensure you’re meeting your daily needs.9

A daily multivitamin is a great insurance policy to ensure you’re getting all the vitamins and minerals you need. Considering over 50% of food consumed by Canadians are ultra-processed, packaged foods low in nutrient-density, it’s a wise decision to cover all your bases.

My philosophy when it comes to nutrition is a ‘food first’ approach, ensuring you get the majority of your key nutrients from food. In today’s hectic work and home environment, a multivitamin is a great way to ensure you’re meeting all your micronutrition needs.

Always consult with your healthcare provider to ensure a multivitamin is right for your specific needs.


  1. Ipsos. https://www.ipsos.com/en-ca/canadians-and-multi-vitamins. Accessed July 30th, 2022.
  2. Moretti D., Goede J., Zeder C., et al Oral iron supplements increase hepcidin and decrease iron absorption from daily or twice-daily doses in iron-depleted young women. Blood, 2015, Oct 22; 126(17);1981-9. doi: 10.1182/blood-2015-05-642223.
  3. Poole R., Kennedy O., Roderick P. et al. Coffee consumption and health: umbrella review of meta-analyses of multiple health outcomes. BMJ2017359 doi: https://doi.org/10.1136/bmj.j5024 
  4. Wolde, T. Effects of caffeine on health and nutrition: A Review. Food Science and Quality Management
    30, 2014
  5. Escott-Stump S. 2008. Nutrition and Diagnosis-Related Care. 6th ed. Philadelphia, Pa: Lippincott Williams & Wilkins.
  6. Rowland i., Gibson G., Heinken A., et al. Gut microbiota functions: metabolism of nutrients and other food components. Eur J Nutr. 2018; 57(1): 1–24. doi: 1007/s00394-017-1445-8
  7. Statistics Canada. https://www150.statcan.gc.ca/n1/pub/82-003-x/2019002/article/00002-eng.htm. Accessed July 30th, 2022.
  8. Hinkle S., Zhang C., Grantz K., et al. Nutrition during Pregnancy: Findings from the National Institute of Child Health and Human Development (NICHD) Fetal Growth Studies–Singleton Cohort. Current Developments in Nutrition, Volume 5, Issue 1, January 2021, nzaa182, https://doi.org/10.1093/cdn/nzaa182
  9. Institute of Medicine. Food and Nutrition Board. Dietary Reference Intakes: Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, DC: National Academy Press, 1998

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