How to know if the supplements you’re taking are actually working

supplement bottle in question mark
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According to the National Institutes of Health, the majority of Americans regularly take at least one supplement, including vitamins, minerals, herbals and botanicals, amino acids and enzymes. While supplements can’t replace a healthy diet, research has found that some dietary supplements can be helpful in promoting overall health and can also be beneficial for specific health conditions.

But how do you know you’re getting the most out of the supplements you’re taking?

How to know if you are vitamin deficient

You might have heard that craving certain foods, like fish, signals that your body is in need of a specific supplement, like fish oil. Or that craving meat might mean you are anemic. However, according to Keri Gans, MS, RDN, CDN, and author of “The Small Change Diet“, there is no scientific evidence supporting this.

She does point out that there are a few symptoms of vitamin deficiency that are obvious, including fatigue and hair loss. A not-so-obvious symptom? Sometimes experiencing gastrointestinal problems might be a sign you need to take a daily probiotic.

However, keep in mind there are many times your body isn’t going to give you any signs, and lab work conducted at your doctor’s office or your own knowledge about your dietary needs are really the only conclusive ways to figure out what nutrients your body is lacking.

For example, someone who doesn’t consume a well-rounded healthy diet might need a multivitamin to fill in nutritional gaps. A vegan may need a B12 supplement because they are not consuming animal products. Or a pregnant woman will likely have to take prenatal vitamins (including folate, DHA, choline and calcium) to support a growing fetus.

Having food allergies or intolerances can also make you a good candidate for taking a supplement. For example, a lactose-intolerant person or a person with a milk allergy might consider adding a calcium and vitamin D supplement for optimal bone health.

But remember, always speak with your healthcare practitioner about any health changes and before starting a new supplement regimen — especially since some supplements can counteract certain medications. The NIH warns that vitamin K can reduce the ability of the blood thinner Coumadin® to prevent blood from clotting. St. John’s wort, often taken to ward off depression, can speed the breakdown of many drugs (including antidepressants and birth control pills) and thereby reduce the effectiveness of these drugs. Antioxidant supplements, including vitamins C and E, might reduce the effectiveness of some types of chemotherapy.

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How to determine if your supplements are working

Most supplements aren’t going to work like magic. Even if they are working, it’s likely you won’t feel any differently, since there aren’t always symptoms to begin with.

Gans does note that there are a few scenarios where you will feel a difference, such as with iron deficiency. If you started supplementing with iron and feel less tired than before you started taking the supplement, it could be working. However, she maintains in this case that it is still important to speak with your doctor and retest your nutrient levels. The same could be said of a probiotic. “For example, if after you started on one your GI issues improved, then one could say the probiotic is helping,” she points out. However, it could also be having a placebo effect.

Quality is key

If you want to ensure that your supplements are going to work, Gans stresses the importance of buying from a reputable brand with third-party certifications.For example, Gans, who works with MegaFood vitamins and supplements, points out that they are “made with real food from trusted farm partners plus added nutrients and offer up to nine certifications for purity and safety.” Additionally, “The company tests for over 125 herbicides and pesticides, and is the only supplement brand to have its entire line Certified Glyphosate Residue Free,” she adds. “Look for companies like MegaFood that craft high-quality supplements so that you know you are giving your body the best.”

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Also, remember that supplements are never going to replace a healthy diet. Just as their name implies, they serve to supplement it.

While supplements are great, nothing can replace real foods. Check out our video on vertical aeroponic farming — aka, farming of the future.