Posts Tagged “science of weight loss”

Popular Weight Loss Supplements Reviewed

Popular Weight Loss Supplements Reviewed

As we train the next generation of of fitness professionals at SFE Academy, we often get emails sent to us with questions posed to us like “how to lose weight fast without exercise” or “how to lose weight fast in 2 weeks”.

 

Our reply is always “A balanced diet with plenty of exercise” you need to get the energy balance equation on your side.

 

The supplement industry is big business, we wanted to scientifically analyse the most popular weight loss or weight gain supplements out there to see if the evidence matched the claim…

Garcinia Cambogia

What is it?

Garcinia gummi -gutta is also more commonly known as Gacinia cambogia. A fruit that has a similar shape to a pumpkin but is much smaller and green or yellow in colour. It is widely used in cooking and the fruit is a native of Indonesia.

The claim: 

It can help weight loss.

How it works: 

(-) – hydroxycitric acid (HCA) is a compound that can be found in Garcinia cambogia and is a derivative of citric acid. Research suggests that (-) – hydroxycitric acid (HCA) inhibits the activity f the enzyme adenosine triphosphatase citrate lyase which plays a role in the synthesis of fatty acids in the body. Furthermore, Garcina cambogia is said to increase serotonin release in the brain leading to suppression of appetite.

What does the evidence say?

One study shows that Garcinia cambogia supplementation led to a small reduction in weight of about 2lbs in a period of between 2-12 weeks compared to the placebo control group.  (1, 234567, 8, 9, 10 )

However…

Studies also suggest that Garcinia cambogia supplementation has no statistically significant effect on weight loss. A large study to examine the effect of taking Garcinia cambogia suggest no effect on weight loss at all; (11, 12)

Summary:

Some studies have shown weight loss through Garcinia cambogia supplementation and other have not. The current optimal does levels are currently unknown. One study has suggested a link between supplementation and a reduction in belly fat.

Pyruvate

What is it?

Pyruvate is a 3-carbon intermediate molecule produced in the last step of anaerobic glycolysis.

The claim: Increased energy and weight loss

How it works:

One of the end products of anaerobic glycolysis that takes place in the cell and responsible for part of our energy production systems carries carbon atoms into the mitochondria for the Krebs cycle and is also responsible for the production of acetyl co-enzyme A (acetyl-CoA). The current theory for supplementation is that by having more pyruvate available for the mitochondria, you are increasing its energy production capacity. There, increasing metabolic rate and acting as a fat burner.

What does the evidence say?

Studies have suggested that pyruvate supplementation does not have any effect of fat loss (16,) one study showed a decrease in body weight and fat mass. However, this result should be interpreted carefully as the study group also participated in a vigorous exercise program along with pyruvate supplementation, so it could be that increased exercise regime that is producing the weight loss. (13, 14, 15, 171819)

Summary:

Pyruvate supplementation does not show any effect on reducing fat mass or promoting weight loss. Nor is there any evidence that total cholesterol, blood pressure, training volume or muscular power out are affected in any way by

Green Tea

What is it?

Green tea is made from the leaves of the Camellia Sinensis plant. The difference between Green tea and normal black tea is that the green tea leaves have not been processed.

The claim: Reduces body fat helps weight loss

How it works

Green tea contains many antioxidants. One such molecule called epigallocatechin gallate (EGCG) this has an affect on adipogenesis (fat cell production) and lipolysis (fat burning)

What does the evidence say?

Studies do suggest that Green Tea does increase fat burning and promote fat loss over the long term (12 weeks or more) however, caffeine contained within the Green tea may also play a role in fat loss too. Caffeine sensitive people should avoid excessive caffeine consumption. (20, 212223 )

 

Summary:

Green tea can increase fat burning. People with a caffeine sensitivity should be aware of the risks of a high caffeine intake.

Conjugated Linoleic Acid (CLA)

What is it?

Conjugated linoleic acid (CLA) is a fatty acid derived from linoleic acid. Linoleic acid is found in many dairy, animal products and oils.

The claim: Increases fat loss and weight loss

How it works

Thought to have a role in energy production, fat burning, inflammation and fat production.

What does the evidence say?

In short, the results are mixed. Some studies in obese populations suggests that CLA is effective at decreasing body fat mass where as other studies suggest that it s not effective at helping to reduce body fat mass in healthy populations (people not classified as obese) Continued and long term consumption of CLA has been attributed to fatty liver, digestive problems and insulin resistance.   (24, 25, 26, 27)

weight gain.

Summary:

Will only produce modest fat loss in some people and can be dangerous in the long term. Taking CLA long term does not prevent weight gain.

Forskolin

What is it?

Found in the plant Coleus forskohlii.

The claim: Promotes weight loss

How it works

Forskolin increases levels of Cyclic AMP (cAMP) in cells which could stimulate fat burning (28, 29)

What does the evidence say?

One study suggests that Forskolin resulted in a decrease in body fat percentage, body fat and it also showed an increase in bone density. However, the same study also saw a rise in testosterone levels amongst the obese men and women tested. Testosterone has a well-documented fat burning effect as well as muscle and bone building properties. This could have accounted for the fat loss seen.

 

Summary:

No clear evidence of Forskolin as a fat burner.

Bitter Orange / Synephrine

What is it?

The real name for bitter orange is ‘Citrus aurantium’ and contains the active molecule p-synephrine.

The claim: Weight loss, appetite control, increased energy

 

How it works

p-synephrine is similar to ephedrine which is a stimulant but does not affect the cardiovascular system in the same way as ephedrine or norepinephrine. (30) p-synephrine/bitter orange is reported to also increase your metabolic rate.

What does the evidence say?

One study looking at the effects of bitter orange on weight loss and mood suggest that the 20 overweight men and women in the study did lose small amounts of weight, but they were also taking caffeine with the biter orange extract pills. This could have attributed to the weight loss seen as caffeine can have potent fat burning effects. There was an increase metabolism for all the men and women in the study. (31)

 

Summary:

There is too little evidence for its fat burning properties to say that it is likely to lead to weight loss. More evidence is needed to conclude its effectiveness either way.

Raspberry Ketones

What is it?

Raspberry ketones are found in raspberries, cranberries and blackberries.

The claim: Helps you lose weight

How it works

The Raspberry ketones have been shown to down regulate some of proteins essential for fat production, storage and fat burning.

What does the evidence say?

The studies on humans are limited. However, some of the studies on rats show that the raspberry ketones do produce a fat burning effect.

Summary:

No evidence that raspberry ketones have any effect on fat burning or weight loss. (32)

Go TopCall Now