Taking a multivitamin, vitamin D and fish oil every day

There is very little doubt that if we eat the diet we were designed to eat and spend adequate time in the sun that we will get most if not all the nutrients we need.

That’s the ideal, but not the reality for a lot of us.  I was recently advised by a group of physicians who are experts in the area that it is reasonable, and probably preferable, for adults to take a low dose multivitamin, 1000 units of Vitamin D and 1000 mg of fish oil every day.  I’m certainly not an expert, so you may want to take the following with a grain of salt, but here’s my take on this advice.


Only 3-4% of Americans reach the DGA (Dietary Guidelines for Americans).  The ADA (American Dietetic Association) conclusions on the subject of multivitamins are basically a) it’s always preferable to get your vitamins from real food and b) given that it doesn’t happen for most people, multivitamins can bridge this nutrient gap.  Don’t fool yourself into thinking that taking a vitamin makes up for not eating right – your best bet is still the marvelous combination of vitamins and minerals found in plant foods.

The NIH consensus statement from 2006 on the subject  of multivitamin/mineral supplements (MVMs) states “the present evidence is insufficient to recommend either for or against the use of MVMs by the American public to prevent chronic disease.”

Where does it leave us?  As Michael Pollan sums it up, the best strategy is to “Eat food, not too much, mostly plants”.  It’s clear that it’s stupid to take high dose multivitamins because of the potential side effects.  (unless you are treating a known deficit). On the other hand, a normal (low) dose multivitamin is probably reasonable to help bridge some nutrient gaps – even though there are no conclusive data that say it will make a difference in preventing disease.

Vitamin D

If you Google “Vitamin D” you get over 13 million hits.  A PubMed search gives you over 49,000 references.   Anyone in medicine (and everyone else as well) has learned by now that Vitamin D is a big deal.  It’s looking more and more like most of us are vitamin D deficient and that being deficient in Vitamin D is bad for you.

The bottom line on this one is that you need to talk to your own doctor (and, yes, you should have one!) about checking your Vitamin D level.  30ng/ml is minimum, but some physicians feel that levels should be kept over 50 or 60ng/ml to optimally decrease the risk of some cancers and other pathologies. 1000IU is probably going to be the new recommended daily dose in the United States.  This one seems pretty straight forward:  a) get your level checked; and, b) it’s ok to take 1000IU per day.

Fish oil

Fish oil is a concentrated source of omega 3 fatty acids i.e. eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA).  Most Western diets are heavy in omega-6 fatty acids, which decreases the ratio of omega-3 to omega-6 fatty acid.  It’s this change in ratio that is thought to increase the inflammatory response.  Supplementing your diet with omega-3 fatty acids changes the balance back to a more favorable (less inflammatory) ratio.  There are good data that achieving this favorable balance in omega-3:omega-6 fatty acids can help prevent (and even treat) cardiovascular disease and may be beneficial in a variety of other inflammatory diseases as well.

So, it makes sense to work on changing this ratio by increasing your omega-3 fatty acid intake.  You can do this by eating around 12 ounces of oily fish (sardines, mackerel, salmon) a week, which is the best option if it’s possible.  For some people that’s not realistic, so the supplement may be a reasonable alternative.   There is one caveat – fish oil supplements can be contaminated, so it’s worth knowing the company (and not just buying the cheapest brand).  Other than the risk of contaminants, there’s not much downside to taking fish oil in a reasonable amount.  1000 mg a day (on days you don’t eat fish) is what is usually recommended.

Mary L. Brandt is Professor and Vice Chair, Michael E. DeBakey Department of Surgery, Baylor College of Medicine and blogs at Wellness Rounds.

Submit a guest post and be heard.

Comments are moderated before they are published. Please read the comment policy.

  • Erica

    Although I don’t have a vitamin D deficiency I’ve been taking 1000iu per day for well over a year which stems more from getting less sunlight each day than we should. And fish oil is just good for health overall. Suggest putting it in the fridge to avoid that fishy after taste!

  • drjebj

    Poor diets are a marker of a more serious problem; most of us no longer sit down with our families to 2 or 3 meals a day and share conversation. Many children who see me cannot remember the last time they ate a vegetable other than potatoes. Instead of learnig to cook at home they make cold cereal and heat up microwave food. Many parents have no idea what their kids are up to because most conversations occur “on the run.” I wish the academics would wake up because vitamins are not going to fix this.

  • http://secondbasedispatch.com Jackie Fox

    Great information! Thank you!

  • stargirl65

    Has any study ever shown that taking a multivitamin improves health?

  • http://www.brightonyourhealth.com Mary Brighton

    Thanks for the interesting article. Vitamin D is a hot topic in the nutrition field. But what I find interesting, here in France, is that doctors ARE looking at vitamin D levels in people during routine blood work…and what is even more interesting to me is the number of people I know who have vitamin D levels below the norm.
    I wonder why?
    Is this phenomenom more common because primary doctors are investigating vitamin D levels? Or is something else going on?
    Thanks for the info on Omega 3 importance. Very important to have Omega 3 oils in the diet…but equally important, check where the fish is from and as the author said, be sure, if you take Omega 3 vitamins, make sure they are not contaminated. Pregnant and breastfeeding women also need Omega 3, but this group must be extra vigilant on where their fish is from, to be sure toxins such as mercury are not ingested in high forms.

    Interesting article and great comment by drjebj: society is in a crises on eating and teaching kids how to eat together, cook and enjoy food! Back to basics…

    Mary Brighton

  • http://nostrums.blogspot.com DocD

    The view that any given patient is deficient in one or more vitamins is almost always speculative; serum vitamin levels don’t mean much when a “low” level may be an adequate one for that patient. This is why studies are almost never able to show health benefit from taking vitamins. Even if there is a sub-population that would benefit, those health improvements are going to take decades to demonstrate.

    The language of the article above shows just how squishy this vitamin advice is (“some physicians feel”).

    The data I’ve seen on omega-3 is mixed so far.

    Bottom line, given our culture of looking for Miracle Cures rather than do the hard work to live and eat healthy, it’s not wise policy to promote these alternatives. It just lets people off the hook from adopting healthy habits.

  • http://www.BocaConciergeDoc.com Steven Reznick MD FACP

    How about eating fresh fish a few times a week, eating plenty of fresh fruits and vegetables and going out for 10-15 minutes of sunlight if you live south of the Mason Dixon line?

    • HJ

      I bought wild Alaskan Coho salmon today…$10.00/lb on sale. The halibut was $20.00/lb, Sockeye-$16.00. The cheap fish is farmed…and then you have to be careful on which fish you buy because of mercury etc…

      Of course there are walnuts and flaxseeds for omega-3 and the special chicken diet eggs that have 250 mg per egg…if you have gotten over that 3 eggs per week restriction.

      If you use sunscreen, it blocks vitamin D-producing UV rays. I believe it is still recommend to limit skin exposure to sunlight. So even if you are south of the Mason-Dixon line, your sunscreen will block synthesis of Vitamin D. For for those of us in grey cloudy climates, taking a supplement is better than going out naked in the cold weather.

  • gzuckier

    I came to the identical conclusions myself. Also, 2 grams of niacin a day to shape up the old lipid profile.

Most Popular