Raise of hands – who takes a dietary supplement? Whether it’s a multivitamin, protein powder, fish-oil, powdered greens – all of those and more fall under the very broad term “dietary supplement.” Today I want to educate you on what a “dietary supplement” is, as well as my personal opinions on the matter.


A dietary supplement is a product taken by mouth that contains a “dietary ingredient” intended to supplement the diet. That may include: vitamins, minerals, herbs or other botanicals, amino acids, and substances such as enzymes, organ tissues, glandulars, and metabolites. Dietary supplements can also be extracts or concentrates, and may be found in many forms such as tablets, capsules, softgels, gelcaps, liquids, or powders.


While the FDA is responsible for oversight of these products, it’s important to know that they are not authorized to review dietary supplement products for safety and effectiveness before they are marketed.

Manufacturers and distributors of dietary supplements do not have to tell the FDA or consumers what evidence they have about their product’s safety or what evidence they have to back up the claims they are making for them.

They do need to use the following label, however, which you’ve likely seen. “This statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.” Only a pharmaceutical drug may make such a claim.


It’s a HUGE market – it’s projected to reach $278 BILLION by 2024, globally! North America alone accounts for over 25% of the global market. That means we are each spending many hundreds of dollars per year on these products!


Supplements can be really helpful for those who are battling specific chronic conditions, but what about for the generally healthy public? And is it money well spent?


One big general problem I have with supplements is that it can lead us down the path of the licensing effect. Remember my blog post about that a few weeks ago? It the thinking that if do something “good”, you’re entitled to do something “bad”. Don’t take a multivitamin thinking that then it’s ok to eat a fast food meal later in the day.


As a former supplement fan, and being in the health and wellness industry, I’m VERY interested in staying aware of the latest science and what it can tell us about the effectiveness of dietary supplements. There’s so many categories, I couldn’t cover them all, but I’ll touch on some that I think deserve a special mention, both for good and not-so-good reasons. Please note that I am not making recommendations for or against any of these supplements. I just want to provide you with some information so you can make an informed decision.



  • High quality studies are showing us time and again that multivitamins are a waste of money. At best, you’re literally peeing your money away. At worst, they can actually be damaging. They don’t ward off cancer, heart disease, help with memory, or increase your lifespan. Most vitamins are water-soluble, so if they aren’t used during the digestion process, the excess will be going down your toilet. Some vitamins (in particular A and E) are fat-soluble, and excess will be stored in your body, potentially leading to toxic levels.
  • Those of us in developed nations who have adequate food supply are getting ample vitamins and minerals that would be found in a multivitamin in the foods we’re already consuming.


Protein Powders

  • In the US, we generally have no problem consuming adequate amounts of protein. If you have specific reasons for wanting to increase your protein intake, protein powders can be a great easy way to make that happen. However, on their own, they won’t help you lose weight or lean down.



  • More and more research is showing how important the microbiome in our digestive tract is. What we know for sure is that taking high-quality probiotics (particularly the Lactobacillus genus) following a round of antibiotics will significantly reduce the incidence of diarrhea. However, probiotics aren’t a digestive cure-all. They haven’t been found to be effective in treating irritable bowel syndrome, among other chronic ailments. Like most other supplements that are actually effective, they can be useful in very specific circumstances, but it’s not necessary to continually take them on a daily basis.


Vitamin C and Zinc

  • Here, in regards to the common cold, research is showing the mega doses of vitamin C will do absolutely nothing to reduce the duration or severity of your cold symptoms. However, there is mounting evidence that zinc might be worth taking, as zinc appears to interfere with the replication of rhinoviruses.


Vitamin D

  • Two recent meta-analysis (a review of a number of studies conducted on the same topic) concluded that Vitamin D supplementation decreased overall mortality in adults.
  • Other research has found that in kids, taking vitamin D supplements can reduce the chance of catching the flu, and that in older adults, it can improve bone health and reduce the incidence of fractures.


Niacin, or Vitamin B3

  • Also known as vitamin B3, niacin is talked up as a cure for all sorts of conditions (including high cholesterol, Alzheimer’s, diabetes and headaches) but in most of these cases, a prescription-strength dose of niacin has been needed to show a clear result.
  • At over-the-counter strength, niacin supplements have only been proven to be effective in helping one group of people: those who have heart disease



  • A recent meta-analysis concluded that, on the whole, taking garlic daily reduces blood pressure, with the most significant results coming in adults who had high blood pressure at the start of the trials.
  • Evidence is mixed on claims that garlic supplements can prevent cancer. Observational studies (which rely on data collected from people already taking garlic supplements on their own) have found associations between garlic consumption and a reduced incidence of cancer, but that correlation could be the result of confounding factors. Controlled studies have failed to replicate that data.


Of course, if your doctor has any specific recommends for you, please follow her advice. Though it’s always a good idea to ask WHY a supplement is being suggested.