Nutritional supplements are a $122 billion dollar industry and the majority of adults take at least one. Yet most research shows them to be of little benefit. Nutrition Diva offers some guidelines for deciding which supplements are actually worth it.
I recently got an email from Brian who wrote: "In episode #28, you talk about multivitamins and calcium. But what about other supplements, like..." And here, Brian listed 25 different nutritional supplements, literally from A to Z, starting with Ashwagandha and ending with zinc. Maybe you have a similar list.
Three out of every four American consumers take a dietary supplement on a regular basis. For older Americans, the rate rises to four in five. And one in three children take supplements.
And we’re spending a lot of money on them. Supplements are a $122 billion dollar industry. And yet, it doesn’t look like we’re getting much of a return on our investment.
The vast majority of the supplements that people are taking are of questionable use.
Supplements don't make us live longer
In 2019, researchers at Tufts University examined survey data on supplement use and health from more than 27,000 individuals, spanning a six-year period. They found that those who reported taking nutritional supplements didn't seem to get any benefit from them in terms of decreased mortality. They didn't live any longer than those who didn't. Those with adequate intake of certain nutrients, including Vitamin A, K, magnesium, and zinc, did live longer than those who didn't, but only if they were getting those nutrients from foods. Those who got them from supplements didn't do any better.
Those with adequate intake of certain nutrients did live longer than those who didn't, but only if they were getting those nutrients from foods.
Now, this particular study is painting with a very broad brush. The researchers didn't look at all the different supplements individually or look in detail at causes of death. But studies on individual nutrients and health conditions—including cancer, heart disease, bone loss, and Alzheimer's—have been largely disappointing.
Although there are some situations where nutritional supplementation is helpful, the vast majority of the supplements that people are taking are of questionable use.
Which supplements should you take?
I’m not going to go through each of the 25 nutrients in Brian’s list one by one in today’s episode. For one thing, I have talked about many of these nutrients (including collagen, glucosamine, Omega 3s, Vitamin K, and many others) in past episodes, You can search our episode archives at nutritiondiva.quickanddirtytips.com. But the other reason is that, if I did go down this list one by one, tomorrow there would be ten emails in my inbox asking about 250 more nutrients.
However, most dietary supplements can be sorted into a handful of categories. So instead of playing whack-a-mole with individual nutrients, let me offer you some guidelines and principles on these larger categories.
Nutrients you can get from food without even trying
A lot of nutrients included in multivitamins, such as thiamine, riboflavin, copper, phosphorus, and selenium, are sufficiently widespread in the food supply that you can easily meet your daily requirements, even if your diet isn't particularly great.
Nutrients you can get from food with a little effort
If you're willing to make even a small effort to eat healthy, you can easily meet the requirements for most of the other essential nutrients. This includes vitamins A, C, E, K, omega-3s, fiber, magnesium, potassium, and zinc, which are among the most commonly taken supplements.
The people who take nutritional supplements are much more likely to have healthy diets, meaning these supplements are largely surplus.
Ironically, the people who take nutritional supplements are much more likely to have healthy diets, meaning these supplements are largely surplus to requirements for these folks. No wonder the supplements don't seem to do much.
There may also be some who take nutritional supplements because they don't really want to eat healthy. They figure they can cover their bases with supplements and then eat whatever they want. But as the 2019 study reveals, those who were meeting their requirements from supplements didn't do as well as those who were meeting them from food.
RELATED: Can I Get My Vegetables in a Pill?
It really is better to get your nutrients from foods rather than pills. And you can do that by eating a variety of fresh fruits and vegetables, fish, eggs, lean meats, dairy, whole grains, legumes, and nuts. (Want an easy way to stay on track? Try the free Nutrition GPA app.)
It really is better to get your nutrients from foods rather than pills.
Nutrients you can’t get enough of from food (and you’ve actually tried)
Even if you are doing your best to eat a variety of healthy foods, there may be a few nutrients that you are still falling short of. Vitamin D is likely to be in this category. Vitamin D is not very widespread in the food supply and most of us don't get enough sunshine to meet the requirement that way. As a result, many people need to rely on supplements for this nutrient.
Vitamin D is not very widespread in the food supply and most of us don't get enough sunshine to meet the requirement that way.
Because B12 is only found in animal foods, vegans usually need a supplement to meet their B12 needs.
Calcium is often in this category as well, especially for those who don't consume dairy. People also sometimes struggle a bit as they get older because the calcium requirement goes up with age. And people generally eat less food as they age. However, it is not necessary (or advisable) to take large doses of calcium. You only need enough to fill the gap between what your healthy diet can provide and the requirement. For most people that is just 250-500 mg per day.
More is (not) better supplements
There's a whole class of supplements based on the flawed notion that if a nutrient is good for you, ten times that much will be ten times better. Nutrients in this category include antioxidants, B vitamins, and zinc.
Not only is there no proven benefit to flooding the body with 1000% percent of the daily requirements, there is a chance of harm.
Not only is there no proven benefit to flooding the body with 1000% percent of the daily requirements, there is a chance of harm. Too many antioxidants from supplements, for example, can stunt the body's own antioxidant mechanisms and impair athletic recovery. Too much Vitamin A can hurt your liver. Too much zinc can actually suppress the immune system instead of boosting it.
Not only are high-dose B vitamins unlikely to give you more energy, but high doses of certain B vitamins can make it hard to detect other serious nutrient deficiencies.
The more different supplements you're taking, the greater the risk that you'll end up overdoing it on one or more nutrients. All the more reason to avoid indiscriminate supplementation.
Wishful thinking supplements
Another large category of nutritional supplements is simply aspirational. These include fat-burning, energy-boosting, anti-aging, stress-relieving, brain-boosting, hormone-balancing, and detoxifying products. Who wouldn't want these effects? And who can resist the idea that we could get these benefits simply by popping a few pills? Apparently, very few of us.
The science behind these types of supplements generally ranges from exaggerated to nonexistent.
The science behind these types of supplements generally ranges from exaggerated to nonexistent. For one thing, it's challenging to scientifically measure whether a product is actually boosting your energy or relieving your stress, cleansing your cells, or rolling back the years. And these effects are notoriously subject to the power of suggestion. (That's why on every one of these supplements, you will find a legally mandated statement that the product is not intended to diagnose, treat, cure, or prevent any disease.)
Hope springs eternal, however, making this one of the most popular categories of supplements—and one of the biggest wastes of money.
Supplements to correct a deficiency
There is one category of supplements that is completely uncontroversial and that's those that are prescribed to correct a medically diagnosed nutrient deficiency. Your doctor may order tests to check for specific deficiencies if you are reporting certain symptoms. Iron and B12 deficiencies are often diagnosed this way. Or, a screening blood test may reveal that you're low in magnesium, vitamin D, or some other nutrients. In this case, supplements absolutely make sense, but you'll want to work closely with your healthcare provider.
Make sure you understand what form and dosage you should be taking, how long you should take it (don't assume that you should just keep taking it forever), and how and when you will recheck to ensure that the issue has been resolved.
Supplements for specific health concerns
It may also make sense to take a supplement if it's been proven to be effective against a specific concern (and that concern actually concerns you). We're not talking about studies in test tubes or with lab rats. We're talking about well-designed studies showing that this specific nutrient offers significant benefits in the prevention or management of a specific disease or condition in humans.
For example, I don't think there's much point in taking a random probiotic to improve general well-being. But if you're taking a course of erythromycin, taking a probiotic containing Lactobacillus rhamnosusGG has been clinically proven to prevent or reduce associated diarrhea.
Obviously, the contenders in this category have to be evaluated one by one. And the evidence is constantly evolving.
Saw palmetto, for example, is a supplement that's frequently promoted for prostate health. Early studies did seem to suggest that it might help reduce BPH. However, as more and more research has been done, those early findings have been overturned.
The story is similar for fish oil and heart disease. The promise of early observations has not held up under more rigorous testing.
Sometimes, the evidence is mixed. Glucosamine, for example, has been found to reduce arthritis pain for some people while it seems to do nothing for others. Because glucosamine is quite safe, it may be worth trying to see if it helps. However, if you can't perceive a clear benefit after 2-3 months, there's probably no point in continuing to take it.
RELATED: Do Glucosamine Supplements Work?
The best advice I can offer for this category is to do your research. The Nutrition Diva archives aren't a bad place to start. There are plenty of other reputable sources of evidence-based information as well, but lots of unreliable ones, too, so be careful about your sources.
I hope you found this overview helpful. If you are considering a nutritional supplement, see if you can identify which of these categories it fits into. This may give you some insight into whether or not it's likely to be worth taking and what type of questions you might want to ask before making your final decision.