There are herbal remedies that are sometimes used to increase appetite in people with undernutrition-type malnutrition.
Cannabinoids have been looked at as a way to stimulate the appetite in undernutrition, especially for people who lose their appetite due to chemotherapy drugs. However, the evidence shows that this is not consistently effective, and so it is not currently recommended. While THC and its analogs may have appetite-stimulating effects in certain cases,[1][2][3] some studies have found that cannabidiol (CBD) products might actually decrease appetite.[4][5][6][7]
In some studies, ginger has been found to increase feelings of satiety and help with weight loss,[8][9] but it can also reduce nausea, which might help increase food intake.[10][11]
For people with overweight and obesity, several different dietary ingredients have been studied for weight loss. A 2021 meta-analysis found that chitosan, glucomannan, and conjugated linoleic acid could assist with weight loss of up to 1.9 kilograms (around 4 lbs).[12] Other supplements have been commonly studied for weight loss, such as green tea extract, garcinia, and L-carnitine, but there is limited evidence to support their effects on weight loss.[13][14][15]