Carnitine powder is a dietary supplement often marketed as being beneficial to both weight loss and exercise enhancement because of its role in metabolism. Carnitine is an amino acid that the body uses to produce fuel for the body cells from dietary intake of fatty acids.
Research on Carnitine
Some animal studies have found that mice given L-carnitine supplements had a decrease in the amount of abdominal fat stored due to a decrease in leptin, a hormone that is associated with obesity. A small human study found those who took carnitine had a 10-pound greater weight loss over the course of 12 weeks, when combined with a diet and exercise program. Carnitine is thought to enhance exercise by supplying fuel for the skeletal and heart muscles.
However, the National Institutes of Health has found that most data over the past twenty years on the positive benefits of carnitine have been found through poorly conducted studies on an inadequate amount of participants. Currently, the agency does not recognize a significant link to carnitine and either metabolic status or improved ability to exercise.
Powder vs Capsules or Liquid
Carnitine supplements are available in three forms: capsules, powder and liquid. Because oral supplements are shown to be less biologically available, many marketers promote the powder or liquid versions. However, neither pills nor powder have been shown to be more beneficial than the other. Both carnitine capsules and carnitine powder are similar in cost, between $.30 and $.70 per gram. Liquids supplements are more expensive. Many people may find the powder easier to use, as it can be blended into a smoothie with other ingredients, such as fruit or vegetable juice.
Carnitine supplements do appear safe for most people, however high doses can lead to side effects such as nausea and vomiting, abdominal cramps, insomnia and a fishy body odor. Supplements may also interfere with medications, so it is important to check with your physician before taking them.