Gwyneth Paltrow is infamous for following weird diets, like the macrobiotic diet, but she also came up with her own plan for losing weight and detoxing. The GOOP Cleanse, named after Gwyneth’s brand, involves only eating one meal a day for 21 days. This is supposed to flush out toxins to help you stay slim and feel healthier overall, as long as you can deal with only having one lonely meal a day for a few weeks.