Rubus idaeus, more commonly known as the red raspberry, is causing a stir in the weight-loss community. Red raspberries produce a chemical called ketones that give the fruit its unique flavor and fragrance. For nearly 100 years, these ketones have been used to add flavor and fragrance to our food and cosmetics. Now, however raspberry ketones are being sold as an herbal supplement with claims that they can treat obesity, aid in weight loss, increase lean body mass and even treat hair loss.
Raspberry ketones are a natural antioxidant. In a healthy diet, antioxidants are essential. When studying animal diets, the results of some studies showed exciting results with the use of raspberry ketones. In the animal studies, scientists noted that the fat processing within the animal's body sped up. Animals also showed reduced fatty tissue, particularly around the liver. This is exciting not only from a weight loss stand point, but for general health as well. Build-up of fat in the liver can lead to serious liver disease. In addition, scientists noted that certain hormones were altered with the use of raspberry ketones. These hormones appeared to increase the body's fat-burning ability. Japanese researchers have also found that raspberry ketones may be good for the skin and hair. In a small scale study, researchers found that some hair regrowth was noted in bald patients using raspberry ketones.
While news about weight loss and hair regrowth are exciting, it is important to note that human test studies of the effectiveness of raspberry ketones have not been conducted for weight loss. Only limited trials have been conducted for skin and hair. With only animal studies to base evidence on, the safety and efficiency of long-term use in humans is unknown. While trials in animals showed decreases in body fat and overall weigh loss, without clinical trials it is unknown whether human bodies react the same way. In addition, dosing is an issue. The correct dosage for effectiveness is unknown and may be affected by a number of factors including age and weight. Finally, due to the lack of human testing, it is unknown if raspberry ketones will cause any drug interactions and whether the use of these supplements is safe during pregnancy and breastfeeding. Side effects are also unknown. Raspberry ketones are chemically similar to some stimulants, so possible side effects could include rapid heart beat, increased blood pressure and jitters.
A few studies on raspberry ketones have been conducted in Japan and Korea over the last decade. Mice and rats were used in testing. While earlier studies with rats were inconclusive, later studies with mice showed that high doses of raspberry ketones changed the way the animals' bodies metabolized fat. Fat-burning sped up resulting in weight loss and leaner body mass, but dosages were very high. The average person consumes less than half of one percent of raspberry ketones in their daily diet. The amount of raspberry ketones given to mice and rats were over 4000 times that amount to result in a 2 percent loss of body fat. In addition, mice who were given high-fat diets showed no weight gain when high levels of raspberry ketones were administered. Raspberry ketones have also been observed breaking down fat cells in test tubes.
Raspberry ketones do show some promise, and this natural antioxidant is no doubt exciting to those wanting to lose weight or regrow hair. It is recommended, however, that consumers proceed with caution. Though levels of raspberry ketones used in cosmetics and as food additives are considered safe, with the lack of human testing it is unknown how the body will react to prolonged high doses of these ketones. Science simply does not yet know whether high doses are safe. Those being sold as an herbal supplement may claim to be the next diet miracle pill, but more research and evidence will need to be gathered before this claim can be considered conclusive. It does appear that very high doses are required for even minimal weight loss. Perhaps a better idea is to concentrate on a well balanced diet containing a variety of fruit and vegetables in their natural fresh forms.