Q. What about leptin supplements, such as those sold on the Internet? continued...
So those “leptin supplements” sold on the Internet don’t actually contain leptin, even though their name can be misleading. Instead, these supplements contain ingredients that are purported to help improve leptin functioning or feelings of fullness.
“A variety of these supplements may be more aimed at total wellness -- things like helping balance other hormones, thyroid hormones -- just optimizing health so that the body begins to respond to leptin more appropriately and allows the person to feel full,” says Duffy MacKay, ND, a licensed naturopathic doctor who serves as vice president of scientific and regulatory affairs at the Council for Responsible Nutrition, a trade group for the supplements industry.
“Some of what you’re seeing is tried-and-true ingredients that are known to cause satiety, things like soluble fibers that have been known for a long time to help make people full,” MacKay says.
As for supplements’ effects on leptin functioning, the picture is less clear, he says. “The leptin science has only been unraveling since 1994, so there are a lot of unanswered questions.”
“No magic bullets are being discovered,” MacKay says. “[But] we shouldn’t write this pathway off as something that we shouldn’t continue to explore.”
Rather than taking supplements that haven’t been fully proven to help, overweight people have other options to aid leptin functioning, experts say. Lustig advises them to reduce resistance to insulin (a hormone that controls blood sugar) and to bring down high levels of triglycerides (a blood lipid).
“Insulin resistance generates leptin resistance. The practical advice is: Get your insulin down,” Lustig says. “How do you get insulin down? The best way is don’t let it go up. Sugar makes insulin go up. We are overdosed on sugar in this country. I think that if we got the sugar down, our insulin resistance would improve and that would help with the weight loss.”
Reducing high triglyceride levels helps, too, Lustig says. Too much triglyceride interferes with leptin’s journey from the blood to the brain via a leptin transporter that allows the hormone into the brain.
“When you’re insulin-resistant, you have high triglyceride [levels]. That’s one of the hallmarks,” Lustig says. “Triglyceride seems to block leptin transport into the brain. In order to make your leptin work, you have to let the signaling occur. The only way to let the signaling occur is to get your triglyceride down.”