Dietary supplements: Benefits and side effects

Dietary supplements are substances that add nutrients, especially micronutrients, to your diet. The addition of these supplements is believed to make up for any deficiencies your diet may lead to and therefore lower the risk of health problems. 

Dietary supplements come in the form of pills, capsules, powders, gel tablets, extracts and liquids. These supplements may contain vitamins, minerals, dietary fiber, amino acids, herbs, phytonutrients and enzymes. Sometimes, supplements are added to everyday foods and drinks to make their regular consumption easier and these products are usually known as fortified foods in the market. 

The market for dietary supplements is not well regulated and often attracts frauds and scams. This has also led to growing disinformation and misinformation online with many questionable products with tall/unsubstantiated claims of health improvement and weight loss gaining widespread popularity. While these supplements may not actively harm you, they may not provide you with any benefits either. This is why you should consume dietary supplements that are recommended by your doctor.

You might have observed that the most popular dietary supplements are actually for micronutrients. This is because micronutrients like vitamins and minerals (unlike macronutrients like carbohydrates) are the ones that most people miss out on because they don’t include sufficient portions of fruits, vegetables, whole grains, nuts and seeds in their diet. This creates an imbalance, which in turn opens the door to diseases. On the other hand, people suffering from malnutrition and malabsorption syndrome can also have major nutritional deficiencies to deal with; dietary supplement may remedy these to some extent.

However, no matter what the underlying issue that leads to the doctor prescribing dietary supplements, it is essential that you follow the instructions precisely. Taking less than the prescribed amounts leads to negative health outcomes and diseases like anaemia if your iron levels are too low, birth defects if a pregnant woman doesn’t get enough folate and weak bones if you are not getting vitamin D or calcium in sufficient amounts. The US Food and Drug Administration (FDA) states that dietary supplements for essential vitamins, minerals, amino acids and enzymes not only make up for nutritional deficiencies but also help reduce the risks of diseases like osteoporosis and arthritis.

(Read more: Diet for anaemia)

Makers and sellers of dietary supplements often claim that their products can aid weight loss by improving your metabolism, curbing your appetite or blocking the absorption of carbohydrates or fats. However, there is little scientific evidence that supports such claims. In fact, as per the US National Institutes of Health, the makers of weight-loss dietary supplements rarely - if ever - carry out studies or trials on humans to confirm the efficacy of their products, appropriate dosage or safety. If studies are done by these makers then they include only a small sample pool and the participants take the supplements for only a few weeks. 

Hence, the long-term effects of weight-loss dietary supplements cannot be proven beyond a reasonable doubt. Instead, there can be some side effects of unsafe or over-consumption of these dietary supplements. This is especially true if you have any underlying conditions or are on medications. Weight-loss dietary supplements can interact with these medications and make your condition worse if you start taking them without the guidance of a doctor. 

(Read more: 7 common weight loss mistakes)

Despite what you may assume or makers of dietary supplements may claim, dietary supplements cannot replace food. Dietary supplements, even the ones that claim to be natural or organic, do not provide the same quality of micronutrients that fruits, vegetables, grains, dairy products, nuts, seeds and other actual foods can. Plus, dietary supplements do not provide the macronutrients your body functions on the basis of, including carbohydrates, fats and proteins. Your main source of nutrition and sustenance, therefore, has to be a balanced diet. There is no replacing food with dietary supplements at all.

(Read more: Tried and tested tips to lose weight)

While too little of micronutrients can cause deficiencies, too much of some can lead to harmful, even life-threatening conditions. This is because dietary supplements often contain active ingredients that can cause strong biological reactions. People often tend to self-prescribe dietary supplements with no input from a doctor, nutritionist or pharmacist, which can lead to overdosing and side effects. Further, since not all dietary supplements are well-regulated, there may be some adulteration if you don’t get the supplements from a reliable source. The following are some of the side effects you can experience if you over-consume dietary supplements or consume the wrong, unsafe or adulterated kind.

(Read more: How drinking water helps with weight loss)

The most common dietary supplements available in the market today are the ones that cater to the most common nutritional deficiencies people face. According to the Harvard Medical School, the following are the most common micronutrients young-adult humans face a deficiency of, their daily recommended dietary allowances (RDA) and the threshold of intake you should not exceed:

According to the American Academy of Pediatrics, if you provide your child with foods from all the major groups then he or she may not need any dietary supplements. However, since micronutrients are necessary for proper growth and development of children, some kids may be in need of dietary supplementation. 

This is especially true if your family is vegetarian or vegan since these dietary patterns can lead to a deficiency of vitamin B12, vitamin D, iron, vitamin A, calcium, zinc and riboflavin. Vitamin D deficiency and rickets occurs in many children in developing countries. Many children are also susceptible to iron deficiency and iron-deficiency anaemia during childhood and may need iron supplements during early years.

It is vital that you take your child to a pediatrician and get a thorough check-up done before getting supplements prescribed. It is also crucial that you administer the precise dosage prescribed by the doctor to prevent the side effects of supplementation.

Dietary supplements can benefit you if you have a limited diet or health issues that lead to nutritional malabsorption or deficiencies. However, over-consumption of dietary supplements can cause a number of side effects in both the long- and short-terms. This is the reason why you should keep the following things in mind if taking dietary supplements:

• Talk to your doctor or healthcare provider about your nutritional needs and take dietary supplements suggested by them.
• Ensure the information and source of the dietary supplements are trustworthy and unadulterated.
• Do not combine two or more supplements or take them at the same time.
• Do not combine or use supplements along with other prescribed or over-the-counter medications.
• Do not use dietary supplements as replacements for food or prescribed medications.
• Do not consume more than the prescribed dosage of dietary supplements.
• If you notice any adverse reactions come up while you are on a dietary supplement, contact your doctor immediately.
• If you are going in for a procedure or surgery, let your doctor know about the supplements you are taking.

Most modern diets lead to nutritional deficiencies because they are not wholesome or balanced and may include unhealthy foods. This is the reason why the use of dietary supplements, especially for micronutrients, has increased in recent years. These dietary supplements, when prescribed by a doctor or nutritionist, can provide you with a lot of health benefits including the prevention of deficiencies, immunity boost, etc. However, the dietary supplement market is not well-regulated and information available about these products may be profit- rather than welfare-driven.

This is one reason why you must only consume dietary supplements as per the recommendations of a doctor. This apart, sticking to the prescribed dose is very important because overdosing can lead to many side effects. Indigestion and stomach upset due to supplement overdose may be a short-term health issue but kidney damage and chronic migraines can lead to long-term problems and decreased quality of life too. As long as you include a dietary supplement on the basis of professional advice and keep your safety in mind, the use of these supplements will be beneficial and advantageous for you.