Overdose Symptoms of 10 Supplements That You Need to Recognize

Every day brings a new headline or TV news segment asking, “Are you getting enough _______?” The blank can be filled in with just about any vitamin, mineral, vegetable, fat — you get the idea. Maybe this explains why the supplement business is booming and shows no signs of slowing down. But that doesn’t mean you should pop pills like candy.

If you’re already popping pills, be on the lookout for signs you’ve gone overboard. We’ve highlighted 10 common supplements and why you should be wary of overdosing.

1. Vitamin C

Close up view of young woman holding ginseng vitamins and minerals pills in hand with capsule bottle on table. High angle view.

If you reach for vitamin C every time you have a cold, you may be taking too much. | iStock.com/diego_cervo

Vitamin C does play a role in supporting a healthy immune system, but going for a huge dose won’t guarantee you never get the sniffles. One 2013 review looked at the research and found the results simply don’t show vitamin C can ward off illness.

Going too far with supplements can lead to the usual nausea and diarrhea, but also less expected symptoms like insomnia and kidney stones. Stick with a salad for your vitamin C.

2. Vitamin D

Woman wearing a pair of round sunglasses

Getting your vitamin D from the sun sounds like a better idea. | iStock.com/Merlas

As long as you get some daily sunshine and eat foods rich with this vitamin, you should be fine without this supplement. With that said, if you are deficient, you’ll want to be careful — vitamin D toxicity can have serious consequences. When you take too much, there’s a chance calcium will build up in your blood, says Mayo Clinic. This can cause stomach issues like nausea or vomiting, or even more serious problems with your kidneys.

3. Creatine

Creatine phosphate supplement in a scoop next to a pile on a black background

Creatine helps build muscle, but make sure you’re not taking too much. | iStock.com

Most gym-goers are familiar with creatine, which is touted as a muscle-building miracle. This amino acid occurs naturally in our bodies as well as meat, but many lifters look to supplements.

The trouble here is the overzealous quest to build muscle leads many guys to take unsafe doses. According to the University of Maryland Medical Center, supplementing your diet with too much creatine can lead to upset stomach, dizziness, high blood pressure, and maybe even kidney damage.

4. Vitamin A

beautiful healthy woman looking in the mirror

Isotretinoin, a powerful acne treatment, contains a vitamin A derivative. | lenanet/Getty Images

Vitamin A is great for your eyes, and it’s especially crucial for pregnant women, as it’s needed to help the baby develop. But because, it’s stored in the liver, it’s very possible to overdose. Healthline notes you can experience anything from blurred vision to jaundice with vitamin A toxicity, and that’s just the tip of the iceberg. Bone pain, mouth ulcers, and hair loss can also occur, and in severe cases, you can damage your liver or kidneys.

5. Fish oil

perforated tray filled with fish oil supplements

Fish oil may be good for your heart, but taking too much can have negative effects. | iStock.com

Research on the benefits of various foods tends to go back and forth, but not when it comes to fish. One 2012 review analyzed seven different studies on the link between fish consumption and cardiovascular disease, finding those who ate the most seafood had the lowest risk.

Unfortunately, results for these pills don’t match up with the real thing. One review found fish oil supplements don’t show any link to a reduced risk of heart disease.

6. Vitamin E

Man pouring out pills from a supplement container with more pill bottles in the background

Too much vitamin E may actually increase your cancer risk. | iStock.com

Antioxidants like vitamin E get a lot of love from the health-conscious crowd for their ability to fight cancer. In a horrifying case, one study looked at how selenium and vitamin E supplements affected the risk of prostate cancer — but it was cut short due to negative results. The published version concluded vitamin E supplements may actually increase the risk of developing the disease.

7. Calcium

orange juice

There’s probably calcium in your orange juice. | iStock.com

We’re all getting a little older, and osteoporosis is a real threat to our bone health as we age. It’s a good thing we have calcium-fortified products and plenty of fresh produce to ensure our bones stay strong. It is possible to have too much of a good thing, though. Medscape cites one example of a woman who was eating tons of calcium-fortified products (think orange juice, granola bars, etc.) and taking supplements. She ended up developing frequent urination, nausea, and mental confusion from the toxic levels.

8. Folic acid

Pregnant woman holding belly

Some pregnant women take folic acid. | iStock.com/tamaravidmar

You’re likely to find this nutrient in your flours, breads, and cereals in addition to your leafy greens and meats. It’s essential for your body to properly function, and it’s especially useful for those who have anemia or deal with digestive disorders, WebMD says.

If you take too much, you’ll be lucky to get away with just an upset stomach, but you could also have skin reactions or seizures. It gets even worse if you have heart problems — too much of this nutrient may raise your risk of an attack.

9. Aconite

man pouring pills into his hand

Aconite can cause herbal poisoning, so it may be best to avoid altogether. | iStock.com

What’s the deal with aconite? According to Consumer Reports, the supplement can lead to nausea, vomiting, irregular heart rhythm, and death. The story goes on to say aconite is actually the No. 1 cause of herbal poisoning in Hong Kong. It’s best to avoid this one entirely.

10. Psyllium

Psyllium seed fiber supplement in a wooden scoop

Taking psyllium for weight loss is not a good idea. | iStock.com

This supplement might sound unfamiliar at first — until you read the ingredient list on a package of Metamucil. According to Healthline, this supplement is 70% soluble fiber and made from the seed husks of a certain plant. Psyllium can be quite beneficial for those who deal with occasional constipation or other gastrointestinal conditions, as long as the dose is reasonable.

Some people reach for these types of fiber supplements as a way to lose weight, which is where things can go wrong. In addition to uncomfortably frequent bathroom trips, SFGate says going overboard on your psyllium intake can lead to a stool blockage, disrupt your electrolyte balance, and damage your kidneys. And Berkeley Wellness says it’ll only help you shed pounds if you manage to decrease your caloric intake anyway. Kale sounds like a better bet.