Weight Loss Supplements Part 1

Here are some weight loss supplements reviewed in a journal article I read recently.

Click here to read part 2.

Caffeine and/or Green Tea

Claim- Caffeine is reported to have fat burning effects. It also increase the breakdown and utilization of fat during exercise. Additionally, green tea contains catechins which have been shown to increase both energy expenditure as well as fat oxidation. Green tea is considered to be high in caffeine.

Research Findings- An increasing number of research studies are demonstrating that green tea increases fat oxidation. This occurs especially during moderate-intensity exercise. These benefits are even more effective in individuals who are considered overweight or obese.

Overall Rating- 3-stars

Conjugated linoleic acid (CLA)

Claim- CLA is a naturally occurring fatty acid. It is claimed that CLA increases insulin sensitivity, decreases plasma glucose, and decreases fat mass.

Research Findings- Much of the best evidence has (unfortunately) has come from animal studies. Obviously this means results and subsequent claims need to be taken with a grain of salt. “However, there is some evidence that prolonged use of approximately 3.5 grams/day can reduce body fat and importantly abdominal bodyfat in moderately overweight people.”

Overall Rating- 3-stars

Carnitine

Claim- Carnitine is naturally occurring in a regular diet. It is stored in the muscles and is important in transporting fatty acids into mitochondria. This is where fat breakdown occurs.

Research Findings- Unfortunately, the primary issue with supplementing with carnitine is that it does not increase levels in muscle cells. Carnintine uptake into the muscles has been shown to increase with the addition of high glycemic carbohydrates. However, ingesting high levels (188 grams in one study) of high glycemic carbs will negate any of the fat loss benefits of the carnitine.

Overall Rating- 2-stars

Alpha-lipoic acid (ALA)

Claim- ALA is a potent antioxident which is claimed to reduce body fat. “There have been many proposed mechanisms of action for ALA reducing fat mass, including the activation of PPAR-gamma, which regulates fatty acid storage and glucose metabolism. It is also a cofactor of many mitochondrial enzymes and has been reported to reduce voluntary food intake as well as increasing energy expenditure.”

Research Findings- Again, unfortunately most of the research on ALA has been performed on rodents. Additionally, some studies have shown some fat/weight loss in obese people who supplemented with 1,800 mg/day. There doesn’t seem to be any solid evidence regarding ALA’s effects on athletic/active people.

Overall Rating- 1-star

Multivitamin

Claim- According to the authors, most athletes get sufficient levels of vitamins and minerals from their daily diet. However, risk of deficiencies increase during periods when a reduced calorie/restrictive diet are followed in an effort to make weight. “B vitamins, vitamin C, vitamin D, iron, calcium, magnesium, and zinc are the most liekly to be low on a calorie-reduced diet.”

Research Findings- A daily, low-dose (no more than the RDA allowance/suggestion) multivitamin/multimineral may be useful, especially when making weight. It is important to note that more is not always better and certain, fat-soluble vitamins can become toxic when ingested in high doses.

Overall Rating- 3-stars

Rating System

1 star- Scientific rationale, however, no supported evidence using human subjects in peer-reviewed journals but some anecdotal reports.

2 stars- Scientific rationale and equivocal published evidence in peer-reviewed journals using human subjects.

3 stars- Scientific rationale and unequivocal evidence in peer-reviewed journals using human subjects.

Paper Referenced

Langan-Evans, C., G. Close, J. Morton. Making weight in combat sports. Strength and Conditioning Journal. 33(6), 25-40. 2011.