Dietary Supplements: What You Need to Know


What is a Dietary Supplement?

Dietary supplements are used to add nutrients to your diet or to lower your risk of health problems. They can contain vitamins, minerals, fiber, amino acids, herbs, or enzymes. Sometimes, they are added to foods and drinks. A doctor’s prescription is not needed to buy dietary supplements. 

Should I Take a Dietary Supplement?

Dietary supplements may give you nutrients missing from your daily diet, but eating a variety of healthy foods is the best way to get the nutrients you need. Some supplements can have an effect on medications you are already taking. Talk to your doctor or dietitian for advice. 

What if I’m over 50?

People over 50 may need more of some vitamins and minerals than younger adults. Your doctor or a dietitian can tell you whether you need to change your diet or take a dietary supplement to get enough of the following:

  • Vitamin B12 helps keep your red blood cells and nerves healthy. As people age, some have trouble absorbing vitamin B12 naturally. 
  • Vitamin D increases intestinal absorption of calcium, iron, and other valuable nutrients. 
  • Calcium works with vitamin D to keep bones strong. 
  • Vitamin B6 is needed to form red blood cells and to process enzymes in the body. 

Are Dietary Supplements Safe?

The U.S. Food and Drug Administration (FDA) checks prescription medicines, and over-the-counter drugs to ensure they are safe and do what they promise. However, the FDA doesn’t consider dietary supplements to be medicines. Therefore, just because you see a dietary supplement on a store shelf, it doesn’t mean it is safe, or that it contains what is written on the label. 

Several private groups such as the U.S. Pharmacopeia (USP),, and the Natural Products Association (NPA), have their own “seals of approval” for dietary supplements. To get such a seal, products must be made in accordance with good manufacturing procedures, must contain what is written on the label, and must not have harmful levels of things that don’t belong, such as lead. 

What About Herbal Supplements?

Herbal supplements are dietary supplements that come from plants. Popular herbal supplements include ginkgo, garlic, and St. John’s wort. Researchers are studying the use of herbal supplements to prevent and treat some health problems, but it’s too soon to know if herbal supplements are safe and useful. Like other supplements, check with your doctor before taking herbal supplements. For some people, these supplements may have an effect when taken with your prescribed medicines.

Supplement Ingredients to Avoid

Individuals who workout heavily or participate in organized sports frequently look to supplements to enhance performance. However, these products may not be totally risk free under all circumstances. If you do choose to use supplements, it’s important to be aware of which ingredients to avoid, such as:


Several sport supplements have tried to market a harmful off-patent drug known as DMAA as a natural constituent of geranium or its extract. However, DMAA has been associated with numerous adverse health events and even several deaths. Despite an FDA ban, some stores and online retailers still sell products that contain DMAA.


This substance has a structure similar to methamphetamine, and its effects have not been studied in humans. Products containing this ingredient have been linked to several failed drug tests, and its addictive and pharmacological properties are unknown.


DMBA is chemically similar to DMAA, which is banned by regulatory agencies in the U.S., UK, The Netherlands and Brazil because of suspected links to strokes, heart failure and sudden death. There are no known safety studies on DMBA and its health effects are entirely unknown. This ingredient may appear on labels under names like “4-amino-2-methylpentane citrate” and “AMP citrate.”

“Andro” Ingredients

Any ingredient with “andro” in the name suggests it is a steroid that can be converted by the body into a hormone. Most major sport organizations have banned such ingredients, which can cause serious side effects, including heart disease, depression and mood swings.


Healthy Tips for You!

Healthy Tip #1

Do not replace foods with dietary supplements as they are not intended to substitute the variety of foods important to a healthy diet. 

Healthy Tip #2

Talk to your doctor before surgery as some dietary supplements may cause changes in heart rate and blood pressure, and increase bleeding.

Healthy Tip #3

While manufacturers suggest a dosage or serving size, you or your doctor might decide that a different amount is more appropriate for you.


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