Weight Loss Pills and Supplements 101: Everything You Need to Know

The weight loss market in the United States is estimated at tens of billions of dollars, with many consumers spending money on weight loss programs as well as weight loss pills and supplements. Unfortunately, millions of people taking weight loss pills aren’t aware of the potential dangers and side effects of these products – or if they actually work.

This article takes a look at weight loss pills and supplements, with input from experts about why they don’t recommend them, the potential side effects of ingredients that some of these products contain, and tips for more healthy ways to lose weight.

For the most part, experts do not recommend taking weight loss pills because of their negative side effects, which include jitteriness, an increased heart rate, and insomnia; as well as stomach discomfort, diarrhea, and constipation. In 2014, the U.S. Food and Drug Administration had issued more than 30 public notifications and recalled several tainted weight loss products, in addition to issuing warning letters and seizing products.

And while some people might see results while taking weight loss pills or supplements, they might gain the weight back once they cease taking them, leaving them back where they started while wasting their money in the end.

Keep in mind that this article is not intended as medical advice. If you decide to take weight loss pills or supplements, it’s important to consult with your doctor first, especially if you have health problems such as heart conditions, seizures or gastrointestinal issues, because taking weight loss pills or supplements can make your condition worse.

How Do Weight Loss Pills and Supplements Work?

According to Allison Wells, a health coach, certified personal trainer and certified nutrition and wellness consultant in Southern California, weight loss pills and supplements typically fall into one or more of these three categories:

  • Increase metabolism to burn more fat
  • Suppress hunger
  • Block or slow the absorption of fat

Depending on the ingredients in the pill, the effect will vary, said Wells, noting that any source of caffeine will increase metabolism and potentially suppress your appetite. For instance, the main purpose of Orlistat, a drug designed to treat obesity, is to break down fat, so less is absorbed into the intestine; and Glucomannan is a fiber, so it’s likely to help suppress appetite.

Candidates for Weight Loss Pills or Supplements

Typically, people with a Body Mass Index (BMI) of 30% or higher would be a candidate for a weight loss pill or supplement, Wells said. Or, someone with a BMI of 27% or higher, if they have a health condition that is better managed with weight loss, such as diabetes or high blood pressure.

Who Should Avoid Weight Loss Pills or Supplements

If you have any existing health conditions or concerns, it’s best to consult with a doctor before taking any new pills or supplements for weight loss, fat burning or appetite suppression, according to Wells, who noted these products should be avoided by the following:

  • People with heart conditions, seizures or hypo or hyperglycemia should avoid anything with excess caffeine, which many weight loss supplements contain

  • People with gastrointestinal issues, such as irritable bowel syndrome or colitis, because many weight loss pills negatively affect the intestines, gastrointestinal tract and bowels

  • People with diabetes should consult with a doctor before taking weight loss supplements

  • People with a history of eating disorders

Why Experts Don’t Recommend Weight Loss Pills or Supplements

According to the U.S. Food and Drug Administration, under the Federal Food, Drug and Cosmetics Act – as amended by the Dietary Supplement Health and Education Act of 1994 – dietary supplement firms do not need FDA approval prior to marketing their products.

Wells does not recommend any specific weight loss pills or supplements because the industry is inundated with unsubstantiated claims, and very little research has been done on the long-term effects of most of these products.

The products that do have some potential for weight loss success are often taken in conjunction with a low-calorie healthy diet, and regular exercise, Wells noted, adding that “these two factors alone are the most effective way to maintain weight loss, without the negative side effects that often accompany weight loss pills.”

In 2014, the U.S. Food and Drug Administration had issued more than 30 public notifications and recalled 7 tainted weight loss products, in addition to issuing warning letters and seizing products, as well as criminally prosecuted people responsible for marketing illegal diet products. To view the list put out by the FDA, visit Tainted Weight Loss Products.

Wells does believe that a smaller dose of caffeine from black coffee or green tea – 100 to 300 milligrams per day, or 1 to 3 cups of coffee – can aid in appetite suppression, give an energy boost for a workout, and speed up the metabolism. “While this may or may not aid in weight loss, it can also have side effects of jitteriness, dehydration, and sleeplessness,” Wells added.

FDA-Approved Weight Loss Pill

According to Wells, the only FDA-approved weight loss pill available without a prescription is Orlistat, which is branded as alli® over the counter, and Xenical® by prescription. It prevents the body from breaking down fat, and when the intestine absorbs less fat, this can aid in weight loss.

Studies have shown an increase in weight loss by less than 3%, Wells said, and the studies for Orlistat were done in conjunction with a restrictive diet and regular exercise, “so the results showed little more weight loss than with these two additional factors on their own,” further adding that some side effects include changed bowel habits, stomach pain, and uncontrollable bowels.

According to the U.S. Food and Drug Administration, Xenical (orlistat 120mg) was approved as a prescription product by FDA in 1999 for obesity management in conjunction with a reduced calorie diet, and to reduce the risk of regaining weight after prior weight loss. In 2007, Alli (orlistat 60mg) was approved for over-the-counter use for weight loss in overweight adults, 18 years and older, in conjunction with a reduced-calorie and low-fat diet.

Common Ingredients in Weight Loss Supplements That Could Help

There are so many “key ingredients” in weight loss pills, noted Wells, who provided the following examples, their claims, and side effects:

  • Caffeine: Caffeine is a stimulant that is often added to diet pills. It’s been claimed to increase metabolism, suppress appetite, and increase energy. It can also cause jitteriness, increase heart rate, and trouble sleeping. The most important thing is to manage your dose and be sure not to take more than 300mg of caffeine per day (this means stimulant beverages and supplements combined).

  • Green Tea Extract: Green tea is a mild stimulant that has also been claimed to promote fat loss. While there is not much research to back this up, high doses can cause stomach pain and constipation.

  • Conjugated Linoleic Acid: This is marketed to help boost metabolism and decrease appetite, though most of the studies were done on animals. Some doctors suggest this supplement is safe in doses of up to 6 grams per day for one year, but other research has shown a negative long-term impact on metabolic health. This is not suitable for anyone with diabetes. Some side effects include stomach discomfort, diarrhea, and constipation.

Most weight loss or fat burner pills work the same by providing significant amounts of caffeine or caffeine based ingredients to increase the heart rate and body temperature as a way of helping you burn more calories, according to Dr. Annthea Fenwick, an expert in nutrition and owner of Achieving Fitness After 50 in Nevada City, California.

“Some will add an appetite suppressant in addition, to help you reduce how many calories you ingest,” said Dr. Fenwick, adding that most of these products will not tell you how much caffeine they are providing, but it is several times greater than the recommended daily intake.

“The result of too much caffeine can be increased blood pressure, heart palpitations, nausea, lightheadedness, and even increased risk of a heart attack.”

Common Ingredients in Weight Loss Supplements That Are Hype

Many weight loss pills or supplements are marketed to have great results, but consumers should be mindful that manufacturers are out to make money.

Therefore, it’s important for people to be aware of the hype before spending their money on these products. Wells has provided a few examples below of ingredients in some these products, how they’re claimed to promote weight loss, what studies actually show and their potential side effects.

  • Garcinia Cambogia Extract: This is a fruit that contains hydroxy citric acid that “may” inhibit fat producing enzymes. “There is no proof that this actually works but is not known to have any negative side effects,” Wells noted.

  • Raspberry Ketones: These claim to help burn fat, but there have been no successful studies done on humans. Some side effects report increased blood pressure and jitteriness.

  • Glucomannan: This is a fiber found in the root of the konjac plant. It absorbs water to form a bulky fiber. This can treat constipation, and possibly slow the absorption of sugar and cholesterol from the gut. It helps in appetite satiation, but side effects include flatulence, bloating, and soft stools. There is insufficient evidence that it aids in weight loss.

Potentially Dangerous Weight Loss Pills and Supplements

According to Wells, the following weight loss pills or supplements on the market are potentially dangerous:

  • Hydroxycut: This supplement, which has had a bit of a checkered past, is not FDA approved and was pulled from the market in 2009 for reformulation after a number of people suffered from liver-related health issues, and even death. To this day, it is one of the most well-known weight loss supplements, but it still comes with a number of side effects, including reports of colitis and liver-related issues, and not much success to back its claims. It is marketed as a weight loss supplement in conjunction with a low-calorie diet and regular exercise. These last two factors are likely the most legitimate tools for successful weight loss.

  • Ephedra: Ephedra – or ma-huang – is an herbal stimulant that was used in weight loss products but is now banned by the FDA. It had severe side effects including mood changes, high blood pressure, stroke, seizures, and heart attack. According to the National Center for Complementary and Integrative Health, the U.S. Food and Drug Administration banned the sale of dietary supplements containing ephedrine alkaloids (compounds found in some ephedra species) in the United States in 2004.

  • Bitter Orange: Bitter orange has been used in the place of ephedra in some weight loss pills. This can have some of the same side effects as ephedra, but because it’s typically used in multi-ingredient supplements, it’s hard to determine its specific effects, Wells said. According to the National Center for Complementary and Integrative Health, bitter orange used in some weight-loss products contains synephrine, which is similar to the main chemical in the herb ephedra, which is banned by the U.S. Food and Drug Administration because it raises blood pressure and is linked to heart attack and stroke

Are Dietary Supplements Safe?

It depends if you need them, where you get them from, and if they’ve been tested for safety, according to Dr. Fenwick. Since 1996, any product labeled as a “dietary supplement” is not reviewed by the FDA for quality, potency, or to verify any claims made by the manufacturer, said Dr. Fenwick, who is also a certified exercise physiologist at the American College of Sports Medicine.

“The only time the FDA looks into a dietary supplement is when enough people have been injured or killed by the product to warrant an investigation,” said Dr. Fenwick, further noting examples such as Ephedra and DMAA, an amphetamine derivative that has been marketed in sports performance and weight loss products.

“The FDA does not approve any dietary supplement,” Dr. Fenwick emphasized, adding that several manufacturers use terms such as “proprietary blend” on their list of ingredients so they do not have to report what is actually in their products.

What Dietary Supplements Do & Don’t Provide

As the term supplement denotes, dietary supplements are meant to provide your body with items missing or lacking in your daily dietary intake, Dr. Fenwick said. However, “most people can get all nutrients they need from their diet,” she noted, adding that certain vitamins are indicated, such as folic acid for pregnant women, Vitamin D for us all in the winter and possible B12 in a vegan diet.

If you choose to take extra supplements, ensure they have been safety tested and discuss it with your health professional, Dr. Fenwick advised, because dietary supplements can have adverse effects with certain medications. 

Supplements can also provide you with too much of certain vitamins and minerals, and taking greater than the recommended daily allowance will not improve your health – in fact, it could hurt it, Dr. Fenwick warned.

Most vitamins are water soluble, meaning you will excrete any unused portion for that day in bright neon colored urine – “literally your money going down the drain,” she said. However, vitamins A, D, E, and K are fat-soluble and are not excreted if you ingest an excessive amount.  “Instead they are stored in your fat cells and in high enough concentrations can become toxic.”

The good news is that a healthy, well-balanced diet will provide your body with all the vitamins and mineral it needs without excess, Dr. Fenwick said, adding that the main reason many people are missing specific vitamins and minerals in their dietary intake is due to the choices they make. 

“Most processed food is stripped of nutrient values,” she explained, further suggesting to choose real food that fuels your body correctly. “True and lasting change takes time and patience. Stick to the basics and be consistent.”

Consumer Shopping Tips for Weight Loss Pills or Supplements

  • Do Your Own Research: If you’re looking for a weight loss supplement, do your research, Wells advised. If something claims to be “clinically proven,” see what the clinical evidence is to support it. Notice how many people are included in the studies, what other factors were at play, such as diet and exercise, and what the length of the study was to prove long-term success.

  • Be Skeptical of Articles Sponsored by the Brand: When you’re looking at articles related to the product you’re researching, make sure the article isn’t sponsored by the brand, Wells recommended. “A key tip here is, if there’s a button to click to purchase the product straight from the website, it’s probably sponsored and therefore likely a biased review.”

  • Research Legitimate Sources: Read medical journals and articles from The Mayo Clinic, WebMD, or Medical News Today for more credible sources of information, because these will give you a better idea of any side effects and legitimate research.

  • Determine the Facts: The Office of Dietary Supplements at the National Institutes of Health has an index to help consumers determine some of the facts about supplements.

Factors to Keep in Mind before You Purchase a Weight Loss Pills

When it comes to trying a weight loss pill or supplement, Wells provided the following 3 important factors to keep in mind before you make a purchase:

  1. First of all, the pills that claim successful results are almost solely in conjunction with a restricted calorie diet and regular exercise. Even the groups that have had success during those trials had minimal weight loss compared to the other individuals with a placebo. Therefore, committing to diet and exercise alone could certainly warrant similar results without the negative side effects that come along with many of these pills.

  2. Second, if you’re trying out a new pill or supplement, weigh the cost, both physical and financial. Most of these have a long list of possible side effects, and there has not been much research proving the effects of long-term use. Taking a pill that may give you a 2% increase in weight loss might not be worth the bowel issues, jitteriness, increased heart rate, or any of the other potential side effects. Remember, this is a money-making market. Everyone is looking for a quick fix or a nudge to get results faster, and it’s typically not sustainable, realistic, or healthy for your body.

  3. Third, definitely consult with your doctor before adding any new pills or supplements to your regimen. It’s very important to understand how they interact with any prescriptions or other supplements you may be taking. You also want to make sure you don’t have any health conditions that would be compromised by using a weight loss pill.

In further advice, Dr. Fenwick said there are manufacturers – mostly of vitamins and minerals and not typically weight loss products – that do pay to have third-party testing of their products to verify quantity and purity of the ingredients listed on the label. “Third-party testing does not verify the claims made by the manufacturer about what the product will do for you.”

5 Simple Tips to Help You Jumpstart Weight Loss

Wells provided the following 5 simple tips to help you jumpstart your weight loss or get you over a plateau – without taking weight loss pills or supplements.

1. Divide your plate in half. Half of the plate should be greens or non-starchy vegetables. Those fibrous veggies will fill you up and give you lots of nutrients without many calories.

2. Drink lots of water. According to the National Institutes of Health, “considerable evidence” shows that an increase in water intake – increased hydration – leads to loss of body weight.

3. Try intermittent fasting. This means not eating for 12-16 hours between dinner one day, and your first meal the following day. Intermittent fasting helps to reduce inflammation in your gut, improves digestion, and can aid in weight loss. Ask your doctor if this is appropriate and safe for you. Not everyone should try fasting.

4. Incorporate cardiovascular exercise. Start your day with 20 minutes of moderate-to-high intensity cardio or a High-Intensity Interval Training workout. Can’t do it in the morning? Try to squeeze it in at lunchtime or before dinner.

5. Try limiting your complex carbohydrates in the evening. Carbohydrates are your body’s first source of fuel, which is great for breakfast or lunch. In the evening, a lighter dinner of protein and veggies may aid in weight loss.

Losing weight can be a frustrating and daunting process, and it can be tempting to take a pill in hopes of it helping to speed up your results, Wells said.

“The reality is weight loss is a journey, and the pills often have more of a placebo effect or negative effect on your body, than the magic you might be hoping to find in it,” she said, adding, “the more consistent you are with diet and exercise, the more likely you are to see results.”

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Alicia Doyle

An award-winning journalist, Alicia Doyle has covered a range of topics, from crime to sports to special education. With an affinity for human interest stories, she has written thousands of articles about inspirational people, events and organizations that have a positive impact on the community and world at large.

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