It’s not clear why some individuals on these medicine lose a whole lot of weight whereas others don’t lose any. “We nonetheless don’t perceive many of the variation in response,” says Ewan Pearson, professor of diabetic medication on the College of Dundee in Scotland. There are a number of identified predictors of how sufferers will fare, although. For example, girls are inclined to lose extra weight than males on GLP-1 medicine, probably as a result of they’ve a distinct fats distribution in comparison with males, or as a result of their smaller common dimension might imply larger publicity to the drug.
And whereas GLP-1 medicine had been first authorised as a diabetes therapy to enhance blood sugar ranges, they’re much less more likely to produce vital weight reduction in individuals with kind 2 diabetes. Researchers have suggested genetics, altered microbiomes, and different medicines that promote weight achieve as doable causes for this. “Loads will depend on an individual’s physiology and biology. We are able to’t anticipate {that a} drug can be a one-size-fits-all for everybody,” says Amy Rothberg, an endocrinologist on the College of Michigan.
GLP-1 medicine result in weight reduction by slowing the motion of meals within the abdomen and by interacting with receptors within the mind to advertise a sense of fullness. Some individuals taking them report much less “meals noise”—they now not have cravings or take into consideration meals on a regular basis. Because of this, they eat much less. Sufferers begin on a low dose that’s steadily elevated every week. Schmidt says some individuals could not reply to the decrease doses however do finally see weight reduction because the medicine is ramped up.
With out life-style modifications, these medicines are more likely to be much less efficient for weight reduction. Novo Nordisk, which makes Ozempic and Wegovy, and Eli Lilly, which makes Mounjaro and Zepbound, stress that the medicine are meant for use alongside a nutritious diet and train. In trials of semaglutide and tirzepatide, the medicines had been paired with a reduced-calorie food plan and elevated bodily exercise. Medical trials are sometimes the best-case situation in relation to a drug’s efficacy as a result of they contain cautious monitoring of members and lots of follow-up visits with suppliers. In actual life, sufferers could not comply with their weight-loss plan as diligently or see their physician as often.
And whereas these medicine assist curb urge for food, they don’t magically get rid of all temptations. In spite of everything, there’s a main social element to consuming meals. “We could eat as a result of it seems to be good, tastes good, we’re within the firm of others, or as a result of it’s obtainable,” Rothberg says. An individual who has these environmental pushes or stimuli competing with the drug gained’t lose as a lot weight as the one that doesn’t should take care of these components, she argues.
Variations in metabolism, or how individuals break down meals and convert it into vitality, is also at play. An individual’s age and hormone operate, in addition to the quantity of bodily exercise they get, can affect metabolism.
Researchers are additionally wanting into whether or not genetic components could clarify a number of the variability in response. In 2022, Pearson and his colleagues published a paper that recognized a gene referred to as ARRB1 that appears to be concerned in glucose management. Once they checked out genetic information from greater than 4,500 adults, they discovered that individuals with sure variants on this gene have decrease blood sugar ranges whereas taking GLP-1 medicine.
