GLP-1 not working? What the science says about non-response

What did @myantiinflammatorylife actually say?

The creator argues that GLP-1 medications underperform when people keep eating the same foods, and offers three fixes: go gluten-free, cut carbs to 120-150g per day, and walk daily. The most specific claim is that "30 minutes of walking, no matter how fast or slow, it lowers cortisol levels by 70%." She also says gluten triggers immune attacks that cause inflammation, which then blocks weight loss in people with PCOS or insulin resistance. These are not throwaway comments. They are presented as clinical guidance for a large audience.

The creator does get credit for framing dietary change as part of GLP-1 success, which is consistent with how these medications are supposed to work. But several claims range from oversimplified to outright unsupported, and the cortisol figure in particular needs serious scrutiny.

Does the science back this up?

Some of it, partially. The relationship between low-carbohydrate eating and improved insulin sensitivity in PCOS is reasonably well-supported. The rest gets shakier fast.

On carbohydrate intake: a 2012 randomized trial by Marsh et al. in the American Journal of Clinical Nutrition found that a low-glycemic-index diet improved menstrual regularity and insulin sensitivity in women with PCOS compared to a standard healthy diet. A target of 120-150g of carbohydrates is not an unreasonable starting range for someone with insulin resistance, though it is not a universal prescription and the evidence does not produce a single "magic number."

On walking and cortisol: a 30-minute walk does appear to modestly reduce cortisol and perceived stress in some studies. Edwards et al. (2018, Neuroscience and Biobehavioral Reviews) reviewed exercise and stress-hormone responses and found benefits, but reductions of 70% from a single 30-minute walk are not supported in the peer-reviewed literature. That figure is not cited and does not appear to originate from a published study.

On gluten and PCOS: this is where the science largely falls apart. There is no strong clinical evidence that gluten triggers immune-mediated inflammation specifically in people with PCOS who do not have celiac disease or non-celiac gluten sensitivity.

What did they get wrong (or right)?

The gluten claim is the weakest part of this video. The creator says "your body starts to attack the gluten, which then causes inflammation" in people with PCOS. That is a description of celiac disease, an autoimmune condition affecting roughly 1% of the population. It does not apply broadly to people with PCOS or insulin resistance. Conflating immune reactivity to gluten with general PCOS inflammation is not supported by current evidence. A 2021 review by Esposito et al. in Nutrients found no consistent benefit of gluten-free diets in non-celiac individuals for metabolic outcomes.

The "70% cortisol" claim is a red flag. Specific percentage figures like this almost always trace back to a single small study, a misquote, or no study at all. No randomized controlled trial in the published literature supports a 70% cortisol reduction from a single 30-minute walk. Presenting it as fact to 88,000 viewers is irresponsible.

What she gets right: pairing carbohydrates with protein and fiber to blunt glucose spikes is legitimate advice. The general point that GLP-1 medications work better alongside dietary changes is consistent with prescribing guidelines. Recommending daily movement without fixating on step counts is reasonable and accessible.

What should you actually know?

GLP-1 receptor agonists like semaglutide and tirzepatide are not passive medications. Clinical trial data from the STEP and SURMOUNT programs consistently show that participants who made dietary and activity changes lost more weight than those who did not. So the creator's central premise, that diet matters on GLP-1s, is correct.

But dietary advice for PCOS and insulin resistance should come from a provider who has reviewed your labs, not a TikTok video. Going gluten-free without celiac disease or confirmed non-celiac gluten sensitivity is not evidence-based for weight loss and may make it harder to meet fiber and micronutrient targets. A carbohydrate target of 120-150g per day may work for some people with insulin resistance, but it is not a one-size-fits-all recommendation.

If your GLP-1 medication does not appear to be working, the right next step is a conversation with your prescriber about titration, injection technique, dietary patterns, and whether there are underlying conditions affecting your response. Not a gluten-free pantry overhaul based on a social media video.