Phenocal: Benefits, Side Effects, Dosage, and Interactions

Using all-natural ingredients, Phenocal is a popular weight loss supplement.

Peruse any drugstore and you will find shelves of weight loss pill bottles with bright labels touting their claims of removing excess pounds fast. One such weight control supplement is Phenocal, which promises quick results with no negative side effects.

Made with extracts of chromium picolinate for reducing carbohydrate cravings, biotin to aid with metabolism, folic acid to mobilize stored fat, green tea leaf extract for energy, and glucomannan for fiber to help you feel full, Phenocal’s marketers advertise these 100% all-natural ingredients for healthy weight loss. 

Health Benefits

According to the World Health Organization (WHO), worldwide obesity has nearly tripled since the mid-1970s. Currently, more than 1.9 billion adults are considered overweight. With such staggering numbers, weight loss products populate both brick and mortar and online stores as organizations hope to attract those searching for a fix to their health issue.

As one of these products, Phenocal attempts to differentiate itself from its competitors by offering a proprietary blend of natural ingredients and extracts, which could provide certain health benefits.

Raising Metabolism

Phenocal contains fucoxanthin, a pigment found within water life, such as in algae and seaweed. Fucoxanthin has the ability to raise the body’s core temperature, thus increasing your metabolic rate. In a study published in Evidence-Based Complimentary and Alternative Medicine, fucoxanthin was found as a promising nutritional ingredient for metabolism and antiobesity. Clinical research also shows this pigment is considered a safe pharmaceutical ingredient.

Suppressing Appetite

Weight loss supplement organizations market Hoodia gordonii for its famed appetite suppression effect. However, the peer-reviewed evidence to support this claim remains pretty sparse. In a study published in the Journal of Ethnopharmacology, researchers concluded that Hoodia gordonii does indeed provide the desired appetite and weight loss effect, but this might occur because of secondary adverse effects and not from Hoodia gordonii itself.

Regulating Insulin

Another ingredient, chromium picolinate, can help regulate insulin levels. Improper insulin levels can lead to a number of health issues, such as type 2 diabetes, obesity, and hypoglycemia.

In a scientific review published in The Diabetes Educator, researchers found that chromium is an essential mineral that appears to benefit insulin action. Researchers also note that taking 200 to 1,000 micrograms of chromium as chromium picolinate per day can improve blood glucose control. They also found chromium safe for consumption. 

Lowering Cholesterol

A substance in Phenocal, glucomannan, could help you lower cholesterol. According to a meta-analysis of several clinical studies, glucomannan can help lower total cholesterol and LDL cholesterol, but does not appear to affect HDL cholesterol.

Possible Side Effects

Although Phenocal says its ingredients are 100% all-natural and safe to consume, you could experience any of the following side effects when using the product:

  • Choking: Glucomannan can create a choking risk. You should take each supplement with lots of water to make sure you digest the pill properly.
  • Vomiting: If you find yourself feeling nauseated, you should try to eat first and not take Phenocal on an empty stomach.
  • Upset stomach: You might want to experiment with the time of day you take Phenocal. Although a dosage is recommended in the morning, per the product's instructions, this might sit too heavy on an empty stomach. Later in the day could work better as you will have more food in your stomach to offset the supplement's powerful extracts.
  • Headaches: If you experience consistent headaches with Phenocal, you could try lowering the dosage. 

Dosage and Preparation

The dosage for Phenocal is three capsules two times a day with a full glass of water. The first dose should come in the morning around 15 minutes before breakfast, and then four hours later before your mid-afternoon meal.

However, this high dosage could cause stomach issues. You should try lessening the dosage to start and working up to this amount and see if your body can tolerate such a high amount of pills.

What to Look For

You should look for the following when purchasing Phenocal:

  • The Pharmaxa Labs label: Pharmaxa Labs offer Good Manufacturing Practices (GMP).
  • Bogus health claims: Make sure you don't see anywhere on the label that Phenocal can cure or treat a disease. This is a fake bottle of Phenocal and you should instantly discard it.
  • Quality: Look for "Pharmaceutical Grade" on the label.

Other Questions

Does Phenocal live up to the hype of being the number one diet product on the market?

The research shows that Phenocal might not work as well as advertised. Phenocal marketers advertise glucomannan as instrumental in helping you reduce portion sizes as this water-soluble fiber form expands up to 50 times when entering the stomach.

However, in a study published in the Journal of Obesity, researchers effectively concluded glucomannan does not promote weight loss or significantly alter body composition, hunger, and glucose and lipid levels.

Can I take Phenocal when I have a medical condition?

You should talk to a medical professional about your medical history, diet, and exercise schedule before starting on a weight loss supplement to determine if Phenocal might work for you. If you decide to try Phenocal to complement a healthy eating and workout regimen, you should always update your healthcare team with any unfamiliar signs and symptoms you experience.

A Word From Verywell

While Phenocal may help facilitate weight loss, keep in mind that dietary supplements (including weight loss supplements) are not held to the same rigorous testing standards as pharmaceutical drugs, and should always be used with caution. In general, we don't support the use of weight loss supplements, but we do advocate a healthy, balanced diet and regular exercise.

If you're considering taking a weight loss supplement, talk to a healthcare provider about the potential risks involved. A medical professional may also offer alternative solutions to supplements to help you reach your weight loss goals.

6 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. World Health Organization. Obesity and overweight. 2020.

  2. Zhang H, Tang Y, Zhang Y, et al. Fucoxanthin: A Promising Medicinal and Nutritional IngredientEvid Based Complement Alternat Med. 2015;2015:723515. doi:10.1155/2015/723515

  3. Smith C, Krygsman A. Hoodia gordonii: to eat, or not to eatJ Ethnopharmacol. 2014;155(2):987‐991. doi:10.1016/j.jep.2014.06.033

  4. A Scientific Review: The Role of Chromium in Insulin Resistance. Diabetes Educ. 2004;Suppl:2‐14.

  5. Sood N, Baker WL, Coleman CI. Effect of Glucomannan on Plasma Lipid and Glucose Concentrations, Body Weight, and Blood Pressure: Systematic Review and Meta-Analysis. Am J Clin Nutr. 2008;88(4):1167-1175. doi:10.1093/ajcn/88.4.1167

  6. Keithley JK, Swanson B, Mikolaitis SL, et al. Safety and Efficacy of Glucomannan for Weight Loss in Overweight and Moderately Obese Adults. J Obes. 2013;2013:610908. doi:10.1155/2013/610908

By Jennifer Purdie, M.Ed, CPT
Jennifer Purdie, M.Ed, is a certified personal trainer, freelance writer, and author of "Growth Mindset for Athletes, Coaches and Trainers."