It’s not clear why some individuals on these medication lose a variety 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 drugs on the College of Dundee in Scotland. There are just a few identified predictors of how sufferers will fare, although. As an illustration, ladies are inclined to lose extra weight than males on GLP-1 medication, probably as a result of they’ve a distinct fats distribution in comparison with males, or as a result of their smaller common dimension may imply increased publicity to the drug.
And whereas GLP-1 medication have been first authorized 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 drugs that promote weight acquire as potential causes for this. “Rather a lot is determined by an individual’s physiology and biology. We are able to’t anticipate {that a} drug will likely be a one-size-fits-all for everybody,” says Amy Rothberg, an endocrinologist on the College of Michigan.
GLP-1 medication 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 might not reply to the decrease doses however do finally see weight reduction because the remedy is ramped up.
With out way of life modifications, these drugs 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 medication are meant for use alongside a nutritious diet and train. In trials of semaglutide and tirzepatide, the drugs have been paired with a reduced-calorie food regimen and elevated bodily exercise. Scientific trials are sometimes the best-case situation in relation to a drug’s efficacy as a result of they contain cautious monitoring of contributors and plenty of follow-up visits with suppliers. In actual life, sufferers might not comply with their weight-loss plan as diligently or see their physician as repeatedly.
And whereas these medication assist curb urge for food, they don’t magically remove all temptations. In any case, there’s a main social part to consuming meals. “We might 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 out there,” 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 cope with these elements, she argues.
Variations in metabolism, or how individuals break down meals and convert it into vitality, may be at play. An individual’s age and hormone perform, in addition to the quantity of bodily exercise they get, can impact metabolism.
Researchers are additionally trying into whether or not genetic elements might clarify a few 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. After they checked out genetic knowledge from greater than 4,500 adults, they discovered that folks with sure variants on this gene have decrease blood sugar ranges whereas taking GLP-1 medication.