01/07/2013 03:28 pm ET

Can Multivitamins Help Us With Cancer Risks?


When I talk to people about supplements, most people have either been on a multivitamin in the past or are currently on one. Even people who are not really into vitamins and supplements do not balk at the concept of multivitamins for either themselves or their family members.

Being that this is one of the most commonly used supplements, researchers have pored over the idea as to whether multivitamins are, in fact, good for our health. When you do a search on the Internet, there are abundant studies that suggest both for and against vitamins -- so what are we to make of all the results?

Should we or should we not take multivitamins?

When patients first come into my clinic of integrative medicine in San Jose, Calif., I usually will go through their medical history, family history, and also their diet patterns. Based on the information, I can then help the patient decide on whether or not to take a multivitamin.

The major determining factors for me in regards to advising whether my patient takes a multivitamin or not are their health history of prior diseases or potentially impending diseases, their family history of cancers or other serious diseases that seem to recur over and over in their family members, and also whether the patient eats a lot of foods that come straight from mother nature (such as vegetables, fruits, nuts, legumes, whole grains, etc.).

If a patient is generally healthy and has a family history that is not concerning and eats a wide array of mother nature's foods, then I generally would not recommend a multivitamin for that patient. This is because if you are healthy and are able to get your nutrients from your foods, that should be the method in which you should be getting your vitamins and minerals. For those who are concerned that they are getting a lot of nutrients but might be missing a few here and there, I will generally advise the patient to get a natural multivitamin and take it once or twice per week as a gap-filler for some rare missing nutrients in his or her diet.

For those people who are older and do not eat a healthy, balanced diet, I would generally recommend taking a natural, food-based multivitamin that is not excessive in the percentage of daily allowances of the vitamins and minerals. These patients should take the multivitamin at the suggested dosing about once a day or every other day. However, with these patients, I generally still try to encourage them to just eat a more balanced diet so that they can take less of the multivitamin.

Despite the above-mentioned general rules for multivitamin usage, I still recommend that all you readers simply ask your physician about this topic, because whether you should be taking a multivitamin or not is truly dependent on your own specific medical history and your diet.

The reason I bring this up is that there are still questions as to whether the more synthetic types of multivitamins might do more harm than good. Therefore, it's a good idea for you to bring your multivitamin to your doctor and see if the one you are taking could potentially be harmful to you based on your medical history. This way, your doctor can see if you are taking a multivitamin that is too synthetic and thus potentially harmful, and can help break down the nutrients on the label for you to see if certain dosages in that multivitamin are too high or too low for your specific medical history.

One special category of people I would like to discuss further with regards to multivitamins is those with cancer or a family history that places them at high risk for cancers. When it comes to multivitamins and cancers, the debate has been back and forth -- even the study results have been back and forth. The unfortunate thing is that some of these studies use more synthetic vitamins, thus, it makes it hard to see whether the more natural forms seem to be worthwhile or not in a lower-dosage format and used as a gap-filler -- which is how multivitamins should be used, in my opinion.

Let's use a recent study as an example of what I mean by saying that we need further studies in natural vitamins that are low in dosage to be used as gap-fillers. In October/November of 2012, a study was published in the Journal of American Medical Association that looked at multivitamins and cancer again, but this time in lower dosages of vitamins and minerals.[1] Results published from the Physician's Health Study II, looking at 14,641 male physicians over a decade, saw an 8 percent reduction in total cancer risk when these physicians took a low-dosage vitamin and mineral multivitamin. There were no significant reductions in any given specific cancer type, but rather there was an overall 8 percent reduction in cancers in general.

This study is interesting to me because it shows that perhaps we need more studies looking at multivitamins as gap-fillers at lower dosages because many of the negative studies in the past used higher-dosage synthetic vitamins, which clinically we know are not a good idea, anyway.

What I would love to see are more studies looking at the types of vitamins we actually utilize clinically, which are the lower-dosage, natural multivitamin forms. This way, we can get more information on the true health impacts, from these natural, low-dosage multivitamins used as gap-fillers, in those whose goals are to eat a well-balanced diet. After all, this ultimately is how we should be using these vitamins in real life, anyway.


[1] Gaziano JM, et al. "Multivitamins in the Prevention of Cancer in Men: The Physicians' Health Study II Randomized Controlled Trial." JAMA. 2012;308(18):1871-1880.

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