Dietary Supplements: Everything You Need to Know

Dietary supplements are products designed to supplement the diet and provide nutrients not consumed in sufficient quantities through food alone. Supplements play a crucial role in bridging the gap between the nutrients needed and those able to be consumed through daily diet. They can provide essential nutrients for fueling bodily functions and supporting overall health.

The benefits of dietary supplements are numerous. They can help to improve the immune system, support heart health, promote bone strength, and provide antioxidant protection. Additionally, supplements can help to enhance athletic performance, reduce stress and anxiety, and even aid in weight loss efforts.

However, there are also risks associated with the use of dietary supplements. Consuming too much of certain nutrients is harmful, and some supplements can interact with medications or cause adverse reactions.

What Is a Dietary Supplement?

A dietary supplement is a product that includes nutritional ingredients such as vitamins, minerals, herbs, botanicals, or amino acids to address specific dietary deficiencies or support a particular health condition. These supplements can come in various forms, including pills, capsules, tablets, powders, and liquids.

What is a Dietary Supplement
What Is a Dietary Supplement?

The benefits of dietary supplements are numerous and can vary depending on the type of supplement and the individual’s needs. For example, some supplements can help to support the immune system, promote heart health, improve brain function, and reduce inflammation. Others can support weight management, athletic performance, or bone health.

What Is the Other Term for Dietary Supplement?

Another term for dietary supplements is “nutritional supplements” or “food supplements.” These three terms are often used interchangeably.

What Does a Dietary Supplement Do?

A dietary supplement provides essential nutrients that are lacking in the diet. The kind of supplement and its specific benefits vary depending on an individual’s nutritional needs and health goals.

What does a Dietary Supplement do
What Does a Dietary Supplement Do?

Supplements for nutrition can support an individual’s overall health and well-being by providing nutrients that are not consumed in sufficient quantities through food alone. For example, individuals who follow a vegan or vegetarian diet must supplement with vitamin B12, as it is primarily available in animal products.

Supplements can also address specific health concerns or enhance athletic performance. Omega-3 fatty acid supplements support heart health, while creatine supplements improve muscle strength and endurance in athletes.

Finally, some supplements provide antioxidant protection, support immune function, and reduce inflammation. Others promote cognitive function or support healthy aging.

What Is the Importance of Dietary Supplements?

Dietary supplements play a vital role in helping individuals bridge the gap between the nutrients they need and those they consume through their daily diet. 

Many people struggle to obtain all the essential vitamins, minerals, and other nutrients their body requires from food alone. Dietary supplements provide a convenient and effective solution to help individuals meet their nutritional needs.

Individuals can support their overall health and well-being by supplementing with vitamins, minerals, and other nutrients. 

Supplements can also help address specific health concerns or prevent nutrient deficiencies leading to chronic diseases. For example, calcium supplements can help support bone health, while omega-3 fatty acid supplements can help reduce the risk of heart disease.

What Are the Uses of Dietary Supplements?

Dietary supplements have various uses and can benefit individuals with nutrient deficiencies, dietary restrictions, or specific health concerns.

One of the primary uses of dietary supplements is to address nutrient deficiencies. For example, individuals who do not consume enough calcium in their diet take calcium supplements to support bone health. Similarly, individuals who follow a vegan or vegetarian diet take vitamin B12 supplements to prevent deficiency.

Supplements can also be used to support specific health concerns or to prevent chronic diseases. For example, omega-3 fatty acid supplements can help to lower the risk of heart disease, while folic acid supplements can help to prevent congenital disabilities.

Some supplements can provide other health benefits beyond what the body can produce. For example, probiotics supplements can improve gut health and support immune function, while melatonin supplements can improve sleep quality.

What Are the Common Types of Dietary Supplements?

Common types of supplements for body health include Vitamin D, magnesium, probiotics, fish oil and multivitamins.

  1. Vitamin D
  2. Magnesium
  3. Probiotics
  4. Fish oil
  5. Multivitamin
What are the common Types of Dietary Supplements
What Are the Common Types of Dietary Supplements?

1. Vitamin D

Fat-soluble vitamin D aids the bones and teeth by helping the body absorb calcium. It also has other functions, such as supporting the immune system and reducing inflammation.

Fatty fish, liver, and egg yolks are naturally rich in vitamin D. Some foods like milk, orange juice, and breakfast cereals are also be fortified with vitamin D.

Most people rely on sunlight exposure as their primary source of vitamin D, as the body can synthesize vitamin D when the skin absorbs UVB radiation from the sun.

An example of why someone takes a vitamin D supplement is if they live in a region with limited sun exposure, such as during the winter months or in northern latitudes. Vitamin D synthesis in the body requires adequate sunlight exposure, so people living in regions with limited sun exposure do not get enough vitamin D from sun exposure alone.

2. Magnesium

The mineral magnesium is essential in many bodily functions, including protein synthesis, muscle and nerve function, and blood pressure regulation. It is involved in over 300 bodily processes that keep the cardiovascular, immune, and nervous systems running efficiently. Magnesium can be obtained through the diet by consuming foods such as green leafy vegetables, nuts, seeds, and whole grains. 

A specific health condition that can cause magnesium deficiencies is gastrointestinal disorders, such as Crohn’sCrohn’s disease, celiac disease, and irritable bowel syndrome (IBS). These conditions can affect the body’sbody’s ability to absorb magnesium properly, leading to low magnesium levels. People with type 2 diabetes are also at risk of magnesium deficiency due to increased urinary excretion of magnesium.

3. Probiotics

Probiotics are living, bacterial microorganisms that are beneficial to gut health and can help to support immune function. These probiotics are found naturally in fermented foods such as yogurt and sauerkraut but can also be obtained through probiotic supplements.

Probiotics can help to improve digestion, reduce inflammation, and enhance immune function. They are a common type of dietary supplement. They can be crucial for individuals with digestive issues or those taking antibiotics, which can kill off beneficial gut bacteria.

Someone takes a probiotic supplement if they are experiencing digestive issues, such as bloating, gas, or diarrhea. Probiotics can help alleviate these symptoms by restoring beneficial bacteria balance in the gut.

4. Fish Oil

Fish oil is a dietary supplement in oily fish like salmon, mackerel, and sardines. Fish oil is a source of essential omega-3 fatty acids that the body can’t produce on its own. Omega-3 fatty acids are anti-inflammatories, so they benefit heart health by reducing the risk of cardiovascular disease. 

Omega-3 fatty acids in fish oil supplements can help reduce triglyceride levels. They can also alleviate other risk factors for heart disease, including high blood pressure and inflammation. As such, individuals with high triglyceride levels often take fish oil supplements.

5. Multivitamin

A multivitamin is a dietary supplement that contains a combination of vitamins and minerals. A multivitamin is intended to help fill nutrient gaps in the diet and ensure the body has all the nutrients necessary for optimal health. Multivitamins come in various formulations, including those designed for specific age groups, genders, and health needs. 

The most common reason to take a multivitamin is if an individual has a restrictive diet, such as a vegan or vegetarian diet. Some people take multivitamins to support their immune systems.

How to Choose the Best Dietary Supplement?

When selecting a dietary supplement, conducting thorough research and making an informed decision is crucial. One key factor to consider is the brand’sbrand’s reputation. Choose a reputable brand with a history of producing high-quality supplements, as they are more likely to provide a safe and effective product.

Another essential step in selecting a suitable dietary supplement is checking the ingredients. Ensure the supplement contains the required vitamins, supplements, or nutritional products. Examining the complete list of ingredients can help determine if the supplement is appropriate for dietary needs and whether there are any harmful additives or fillers.

Certifications are also vital to consider. Look for supplements certified by third-party organizations, such as the United States Pharmacopeia (USP) or NSF International, which ensure that they are tested for the supplement’s safety and quality. 

Before starting any new supplement regimen, it is advisable to consult with a healthcare professional, such as a doctor or registered dietitian, who can provide guidance on whether a supplement is safe and beneficial for specific nutritional needs.

How Long Does It Take for a Dietary Supplement to Work?

The length of time it takes for a dietary supplement to work varies depending on the supplement and the individual taking it. Some nutritional supplements, such as vitamins and minerals, can provide noticeable effects within a few days to a week. Others, such as probiotics or herbal supplements, can take weeks or months to produce apparent benefits.

For instance, taking vitamin C supplements can result in a noticeable improvement in immune function within a few days. Similarly, taking iron supplements can enhance energy levels and reduce symptoms of anemia within a week or two. However, probiotics can take several weeks to improve digestive health and boost the immune system, as they require time to populate the gut with beneficial bacteria.

How Long Should You Take Dietary Supplements?

The length of time to take a dietary supplement depends on the supplement and an individual’s nutritional needs. 

Long-term intake is typical for food supplements such as vitamins and minerals to maintain optimal levels in the body. Other dietary supplements, such as herbal supplements, can be taken for a shorter period to address specific health concerns.

However, the safety and efficacy of dietary supplements are not always supported by scientific evidence, and taking them long-term is not always necessary or beneficial. Some supplements can cause adverse effects if taken in high doses or for an extended period.

What Are the Different Forms of Dietary Supplements?

The different forms of dietary supplements include capsules/tablets, softgels, powders, liquids, gummies, and sublingual tablets.

  1. Capsules and tablets: Capsules, made from gelatin, contain supplements in powder form, while tablets are compressed powders. Both are designed to be swallowed with water.
  2. Softgels: These are similar to capsules but are made with a gelatin outer layer and a liquid or oil center. Softgels are commonly used for supplements that are difficult to absorb in powder form.
  3. Powders: Supplements in powdered form can be added to liquids or foods. Examples include protein powders, pre-workout supplements, and meal replacement shakes.
  4. Liquids: Liquid fish oil, minerals, and vitamin dietary supplements can be added to drinks or taken directly.
  5. Gummies: These are designed to be chewed and swallowed. Gummies supplement forms are commonly used for children’s multivitamins, as they are more palatable than capsules or tablets.
  6. Sublingual tablets or sprays: Supplements in this form dissolve under the tongue. Sublingual supplements are commonly used for dietary supplements such as vitamin B12, as they can be absorbed more quickly than swallowed supplements.

What Are the Health Benefits of Dietary Supplements?

The health benefits of dietary supplements varies based on an individual’s nutritional needs, below are some common benefits that one can see. 

  1. Improved nutrient intake: Some people do not consume enough of certain nutrients from food alone, such as vitamin D or calcium. Dietary supplements can fill these nutrient gaps and ensure the body gets all nutrients for optimal health.
  2. Enhanced immune function: Dietary supplements, like vitamin C and zinc, support immune function and reduce infection risk. These nutrients improve the body’sbody’s ability to fight harmful viruses and bacteria.
  3. Increased energy levels: Iron and B vitamins are essential in energy metabolism, boosting energy levels and reducing fatigue. Iron is necessary for hemoglobin production, which carries oxygen in the blood, while B vitamins help convert food into energy.
  4. Improved bone health: Calcium and vitamin D supplements improve bone health and reduce the risk of osteoporosis, characterized by weakened bones. Calcium aids in building strong bones, while vitamin D helps the body absorb calcium more efficiently.
  5. Lowered risk of chronic disease: Antioxidants and omega-3 fatty acids can reduce the risk of chronic diseases including cancer and heart disease. Omega-3 fatty acids lower triglycerides and blood pressure, while antioxidants fight oxidative stress, a critical factor in chronic disease development.
  6. Reduced inflammation: Chronic inflammation is linked to many chronic diseases like heart disease, diabetes, and cancer. Curcumin and omega-3 fatty acids help reduce inflammation in the body.
  7. Improved mental health: Vitamin D is involved in serotonin production, a neurotransmitter that regulates mood and can protect against the effects of stress on the brain. Supplementing with vitamin D can improve symptoms of depression and anxiety in people with low levels of the nutrient. 

What Are the Health Risks of Dietary Supplements?

Although not all dietary supplements carry the same risks, some potential health risks are associated with their use. Potential health risks of dietary supplements include the following.

  1. Interactions with medications: Some supplements interact with prescription or over-the-counter medications, which can lead to harmful side effects of vitamins or reduce the effectiveness of the medication. For example, St. John’s can interact with various drugs, including birth control pills, antidepressants, and blood thinners.
  2. Adverse effects: High doses or long-term use of supplements can cause adverse effects like gastrointestinal upset, allergic reactions, and liver damage. For instance, high doses of vitamin C supplements can cause nausea, diarrhea, and stomach cramps. Some people can also be allergic to certain supplements, leading to allergic reactions such as hives or difficulty breathing.
  3. Toxicity: Fat-soluble vitamins (A, D, E, and K) can be toxic in high doses. Excessive intake of these supplements can lead to various health problems, including liver damage, bone loss, and congenital disabilities. Iron supplements can also be toxic in high doses and cause iron overload, leading to liver damage, heart problems, and other health issues.
  4. Contamination: Dietary supplements can be contaminated with harmful substances, such as heavy metals, pesticides, or prescription drugs. These contaminants can cause adverse effects and are not listed on the supplement label.
  5. Mislabeling: Some supplements do not contain the ingredients listed on the label or include higher or lower amounts of the active ingredient than stated. Many supplements marketed for weight loss or enhanced athletic performance contain banned or unapproved pharmaceutical ingredients not listed on the label.
  6. Lack of regulation: The manufacturing and labeling of dietary supplements are not as tightly regulated as pharmaceutical drugs. Nutritional supplements do not undergo the same rigorous testing and quality control as drugs, which can increase the risk of adverse effects.

Why Is the Consumption of Dietary Supplements Considered Risky?

The consumption of dietary supplements is considered risky because they are not regulated in the same way as pharmaceutical drugs. Unlike drugs, which must undergo rigorous safety testing before being approved for use by the general public, dietary supplements are not required to go through the same testing level before being sold to consumers. This lack of regulation can lead to several potential risks for those who take dietary supplements.

How Should You Use Dietary Supplements?

Following a few fundamental guidelines is essential when using dietary supplements to ensure their safe and effective use.

First, choose high-quality supplements from reputable manufacturers that have been third-party tested. Look for food supplements with the USP (United States Pharmacopeia) or NSF (National Sanitation Foundation) seal, indicating that the supplement meets specific quality standards. 

It’s also important to read the supplement label carefully and follow the recommended dosage instructions. Avoid taking more than the recommended dose, which can increase the risk of adverse effects. 

When taking multiple supplements, be aware of potential interactions between the dietary supplements and any prescription or over-the-counter medications you are taking. 

Those with chronic health conditions or taking medication should always consult a healthcare professional before starting any new supplement regimen.

When Is the Best Time to Use Dietary Supplements?

The best time to use dietary supplements largely depends on individual needs and health goals. Generally, it is recommended to use nutritional supplements to complement a healthy and balanced diet and address specific nutrient deficiencies or health conditions.

For example, some people benefit from vitamin D supplements during winter when sunlight is limited. Similarly, others require iron supplements to address anemia or folic acid supplements during pregnancy to support fetal development.

How Are Dietary Supplements Regulated?

In the United States, the Food and Drug Administration regulates supplements according to the Dietary Supplement Health and Education Act (DSHEA).

Under DSHEA, the FDA regulates health supplements as a special category of food rather than drugs, meaning that dietary supplements are subject to lesser safety and efficacy standards than prescription drugs. 

While the FDA can act against manufacturers of unsafe or mislabeled dietary supplements, it does not have the same authority to regulate supplement manufacturers as they do drugs because nutritional supplements are generally considered to be lower-risk than drugs and are used for different purposes.

Why Is Dietary Supplement Regulated by FDA?

The FDA regulates supplements to ensure they are safe, properly labeled, and meet specific quality standards.

Dietary supplements are different from drugs and conventional foods, and the regulation of supplements helps to protect consumers from potentially harmful products and misleading claims. The FDA requires that supplement manufacturers follow current Good Manufacturing Practices (cGMPs) to ensure their products are produced safely and consistently.

The regulation of dietary supplements also helps to promote transparency and accountability in the supplement industry. 

Manufacturers must provide accurate and truthful information about their products, and the FDA has the authority to take action against any supplement found to be unsafe or misbranded.

Are All Dietary Supplements Regulated by the FDA?

The FDA regulates all dietary supplements under the Dietary Supplement Health and Education Act (DSHEA) of 1994. However, it’s important to note that the regulation of dietary supplements differs from that of drugs and conventional foods.

Unlike drugs, dietary supplements do not need FDA approval before they are marketed. Instead, supplement manufacturers are responsible for ensuring their products are safe, properly labeled, and meet quality standards. 

Is It Good to Take Dietary Supplements Every Day?

The answer to whether it is good to take dietary supplements every day is complex, as it depends on various factors such as individual needs, health status, and the type of supplement in question. In some cases, taking dietary supplements daily can be beneficial, while in others, it can be unnecessary or harmful.

For example, some individuals, such as pregnant or breastfeeding women, require daily supplementation with certain nutrients, such as folic acid or iron, to support a healthy pregnancy or lactation. In such cases, taking dietary supplements every day is recommended and beneficial.

On the other hand, taking high doses of certain vitamins and minerals daily, such as vitamin A or iron, can be harmful and lead to toxicity. Daily herbal supplements can also have potential side effects or interact with medications.

Is a Dietary Supplement a Vitamin?

No, a dietary supplement is not necessarily a vitamin. While some nutritional supplements contain vitamins, they can also include other substances such as minerals, herbs, amino acids, or enzymes.

Are Dietary Supplements Used for Weight Loss?

Yes, dietary supplements are sometimes used for weight loss, but their effectiveness and safety are often questionable. For example, garcinia cambogia is a fruit that grows in tropical regions and is believed to have weight loss properties due to its high hydroxy citric acid (HCA) content. It’s often marketed as a natural aid for weight loss.

The proposed mechanism for how garcinia cambogia aids weight loss is by inhibiting citrate lyase, an enzyme involved in the body’s fat production. By inhibiting citrate lyase, garcinia cambogia can reduce fat accumulation in the body and promote weight loss.

However, the quality and purity of garcinia cambogia supplements can vary greatly, and there have been reports of adulterated or contaminated supplements on the market. Moreover, there have been reports of liver toxicity associated with using garcinia cambogia supplements.

Similarly, green tea extract is thought to have weight loss benefits by promoting fat burning and increasing metabolism. The active compounds in green tea extract are catechins, particularly epigallocatechin gallate (EGCG), which increases levels of norepinephrine, a hormone that helps to break down fat cells.

In addition to promoting fat burning, green tea extract can help reduce appetite and increase energy levels, supporting weight loss efforts. However, while some studies have suggested that green tea extract can aid in weight loss, the evidence is mixed.

Furthermore, high doses of green tea extract supplements can cause side effects such as insomnia, nervousness, and an increased heart rate. 

Are Dietary Supplements Safe?

Yes, dietary supplements are considered safe when used as directed and in conjunction with a healthy lifestyle. However, their use has potential health risks, such as drug interactions, adverse effects, toxicity, contamination, mislabeling, and lack of regulation.

Athletic Insight

Athletic Insight Research


The Athletic Insight Research team consists of a dedicated team of researchers, Doctors, Registered Dieticians, nationally certified nutritionists and personal trainers. Our team members hold prestigious accolades within their discipline(s) of expertise, as well as nationally recognized certifications. These include; National Academy of Sports Medicine Certified Personal Trainer (NASM-CPT), American College of Sports Medicine (ACSM), National Strength and Conditioning Association (NSCA-CPT), National Academy of Sports Medicine Certified Nutrition Coach (NASM-CNC), International Sports Sciences Association Nutritionist Certification.