Beware the Effects of Over-Supplementation

If you’re trying to improve your health, you’ve probably read about different supplements to try. Whether you’re trying to boost your immune system, fight off the effects of aging, improve your focus or otherwise, vitamins, minerals, antioxidants and other supplements can be very helpful.

On the other hand, it’s important to monitor your supplement intake carefully, especially if you eat a lot of fortified food. Some supplements can cause health problems if your intake is too high.

Here’s what to know about over-supplementation and how to avoid it.

Which supplements are dangerous in large amounts?

Water soluble supplements are less risky than others: excess intake is excreted in urine. There are nine water soluble vitamins: “the B vitamins -- folate, thiamine, riboflavin, niacin, pantothenic acid, biotin, vitamin B6, and vitamin B12 -- and vitamin C.” However, that doesn’t mean you don’t need to worry about their effects. For example, excessive vitamin C and zinc causes nausea, diarrhea and stomach cramps. Excessive selenium can also cause gastrointestinal issues, as well as fatigue and even nerve damage.

Therefore, it’s crucial that you watch your supplement intake carefully. The three top culprits are calcium, vitamin D and folic acid. Folic acid is commonly added to fortified products like flour, rice, bread and cereal. If you don’t get enough folic acid, it can harm a fetus during pregnancy. However, if you get more than 1,000 micrograms per day, you run the risk of masking the symptoms of vitamin B12 deficiency, which can cause permanent nerve damage. Fortunately, there’s no need to worry about foods naturally rich in folate.

Vitamin D supports the bones, teeth, mood and more, but it is also dangerous in large amounts. The recommended upper limit for adults is 4,000 IUs per day. If you regularly take more than that, you run the risk of developing heart problems.

Calcium overdoses are also dangerous. “Calcium overdose can impair the functioning of the kidneys, increase the pH of the blood, and can cause nausea and vomiting, confusion or changes in thinking or mentation, itching, and in extreme cases irregular heartbeat.” Calcium isn’t just found in foods and supplements, either—you may get some in antacids and even hand lotions. Generally, adults should get somewhere between 2,000 to 2,500 milligrams of calcium each day.

Hitting the right balance

How do you know whether you need to take a supplement? This can be influenced by many factors, such as your diet (plant-based diets may require extra supplementation) or health conditions. The best way to find out whether you need additional supplementation is to go to your medical doctor and have blood work performed. Depending on the results, you may find that you have a deficiency in one area or another. For example, if you have a vitamin D deficiency, as many American adults do, your doctor might recommend a certain dose for a prescribed period of time. After that, your blood can be retested to evaluate your levels.

Absent issues with health or diet, the best way to get nutrients is to eat whole foods rich in vitamins and minerals. It is very difficult to overdose when you’re getting nutrients from food rather than supplements. If you do need to take supplements, however, make sure that you track your food and other intake. Because large doses can cause serious health problems, it’s best to approach supplementation with caution and medical guidance.

What to eat instead

If you’d prefer to get your nutrients from food, this guide is a great way to source nutrient-dense foods. “Nutrient dense” simply means that you get more nutrients from the same caloric volume of food than you would compared to eating a Big Mac.

Generally, your diet should consist of “fruits, vegetables, whole grains, non-fat and low-fat dairy, fish and seafood, unprocessed lean meat and skinless poultry, nuts and legumes.” That doesn’t mean that you have to give up cheese, bread and chocolate entirely—in fact, these foods have health benefits in moderation—but the bulk of your diet should be focused on whole, unprocessed foods. The more whole foods you eat, the more likely that you’ll have a healthy nutritional balance of all the necessary vitamins, minerals and more.

Ultimately, however, your doctor can best advise you as to whether you need to or should consider supplementing. Always check with a medical professional before starting a new health regime.