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I'm a Pharmacist and These are 5 Supplements to Never Buy Again

Save your money.

When you walk down certain aisles at your local drug store, you see rows and rows of supplements and vitamins. It might make you wonder, "Should I be taking these?" While some people can certainly benefit from supplementing their diets with pills, powders or drops, not all supplements are useful. Some can actually be harmful. Plus, supplements can be expensive, and you don't want to waste money on something that might not actually do anything for you. Even worse, it could interact with medication you're taking. You should always talk to your doctor about what supplements might make sense for you, but here are five supplements that are almost never worth buying. Read on to find out more—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


Vitamin K


Smiling young lady looking at her vitamins

You won't always find vitamin K listed on the nutrition labels of the food you buy at the supermarket, but this vitamin, which is actually a group of vitamins, plays several important roles in your body. The number one thing it does is help create proteins that make your blood clot properly. It's also important for bone health.

That said, it's rare for adults not to get enough vitamin K. Usually when someone has a vitamin K deficiency it's because they have an illness like Crohn's or Celiac disease or they've taken antibiotics for long periods of time. Newborns may also suffer from a deficiency, which is why they're often given a shot of vitamin K in the hospital.

 Most people get plenty of vitamin K from their diet, which means you usually don't need a supplement. Some of the best sources of vitamin K include:

  • Leafy greens, such as kale, spinach, Swiss chard, collards and lettuce
  • Broccoli
  • Brussels sprouts
  • Soybean and canola oils

There are some people who should not take vitamin K supplements. Because the compound is involved in blood clotting, it is not recommended for heart patients who take anticoagulants, or blood thinners, such as warfarin (Coumadin).

RELATED: What Taking Zinc Does For Your Body, Say Experts




Tired young African man using laptop while sitting at the table on a sunny morning.Concept of people working hard home

Caffeine itself is usually not a problem. In fact, it's probably the most commonly taken drug in the world. It wakes up your central nervous system and gives you a jolt of energy. Because of these effects, it is often used in energy drinks and added to other food and beverages, such as water and gum. Up to as much as 400 mg of caffeine a day — about four cups of coffee — is perfectly safe for most people, according to the Mayo Clinic.

The trouble is that many supplements are highly concentrated. It's easy to get too much caffeine. When you take in too much caffeine, it can have negative effects ranging from mild to serious. These include:

  • Restlessness
  • Trouble sleeping
  • Jitteriness, shakiness
  • Irritability
  • Headaches
  • Rapid heartbeat
  • Heightened blood pressure
  • Heartburn
  • Anxiety
  • Dehydration

All in all, if you want to perk up with caffeine, stick to naturally caffeinated beverages like coffee or tea, and keep an eye on the effect they have on you. If you feel jittery or are having a hard time sleeping at night, you might want to cut back.

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Vitamin C

vitamin c supplements

Vitamin C might be the most popular vitamin out there. People often take it as a way to boost their immune system. It's true that our bodies need vitamin C to stimulate white blood cells, the heroes of the immune system. Vitamin C is also important for making collagen, which is found all over your body, such as in bone, cartilage and skin. But it's also probably not necessary to take a supplement. For one, research shows that a vitamin C supplement doesn't stop most people from getting a cold. (Although you might feel sick for a shorter amount of time.) Some people also take mega doses of vitamin C, more than 3,000 mg a day, which could cause diarrhea and an increased risk of kidney stones.

 Most people get all the C they need from foods. Unless your doctor tells you to take a vitamin C supplement, stick the foods high in vitamin C instead:

  • Red peppers
  • Oranges
  • Kiwi
  • Broccoli
  • Strawberries
  • Cantaloupe
  • Tomatoes

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Vitamin E

vitamin e


This one is a little tricky. Vitamin E is important for counteracting the effects of free radicals, supporting your immune system and preventing dangerous blood clots. And the truth is, many Americans don't get enough vitamin E from their diets. But there's also no evidence that lower levels of vitamin E cause any harm. Taking vitamin E supplements, though, does have some drawbacks. It interferes with blood thinners, so patients on warfarin (Coumadin) shouldn't take it and studies also suggest too much can increase the risk of prostate cancer.

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"Antioxidant" is a major health and wellness buzzword. And for good reason: Antioxidants are great for intercepting free radicals (highly reactive molecules) that can damage cells in the body and even affect your DNA. But like most buzzwords, the true meaning can be a little fuzzy. You can find antioxidants in a lot of places like lycopene, selenium and vitamins, C, E and A.

While they're all good for you, studies show it's not necessarily good to take them in supplement form. Research has found that antioxidant supplements can increase your risk of skin cancer and prostate cancer and even interfere with chemotherapy. It can also up your risk of lung cancer if you're a smoker.

 The best way to get antioxidants is through your diet. Some great antioxidant-rich foods include:

  • Broccoli
  • Sweet potatoes
  • Bell peppers
  • Almonds
  • Legumes
  • Oatmeal
  • Apricots
  • Carrots
  • Eggs
  • Tuna
  • Salmon
  • Brown rice

 The supplements on this list fall somewhere on the spectrum between don't do it and don't bother. If you can get what you need by eating nutritious greens, crunchy peppers and peanut butter — and you sure can — then stick to the real stuff and skip the supplements. And to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.

Dr. Shaili Gandhi, Pharm.D., is the vice president of formulary operations at SingleCare


Shaili Gandhi, PharmD
Shaili Gandhi, PharmD, is Vice President of Formulary Operations at free prescription savings service SingleCare. Read more about Shaili
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