@gcbelfast's 'strange but normal' GLP-1 side effects, fact-checked

What does this TikTok actually claim?

Gerard (@gcbelfast) tells his 18.4K viewers that GLP-1 medications cause "little side effects" that "catch everyone off guard" including cold spells, energy dips, appetite changes, and taste changes. He calls these effects "strange but normal" and suggests they happen more when "life gets busy."

The video doesn't specify which GLP-1 medication he's discussing, lumping together what could be semaglutide (Ozempic, Wegovy), tirzepatide (Mounjaro, Zepbound), or liraglutide. That's already a problem since these drugs have different side effect profiles.

Are cold spells and energy dips real GLP-1 side effects?

The clinical trials don't support Gerard's claims about cold spells and energy dips. The STEP 1 trial (Wilding et al., NEJM, 2021) tracking 1,961 people on 2.4mg semaglutide for 68 weeks found fatigue in 11.6% of participants versus 7.9% on placebo.

But "energy dips" and "cold spells" aren't listed among the documented side effects in any major GLP-1 trial. The SURMOUNT-1 trial (Jastreboff et al., NEJM, 2022) following 2,539 people on tirzepatide found nausea (85%), diarrhea (81%), and vomiting (48%) as the most common issues.

Gerard might be conflating rapid weight loss effects with medication side effects. Losing weight quickly can affect body temperature regulation and energy levels, but that's different from direct drug effects.

What about appetite and taste changes?

Here Gerard gets it right. Appetite suppression is literally how these medications work. GLP-1 receptor agonists slow gastric emptying and act on brain appetite centers.

The STEP 2 trial (Davies et al., Lancet, 2021) found that people on 2.4mg semaglutide lost 9.6% of body weight versus 3.4% on placebo specifically because of reduced food intake. Taste changes, while less common, do appear in clinical data.

The SURMOUNT-1 trial documented taste disorders in a subset of tirzepatide users. So Gerard's on solid ground with these two claims, though he could've been clearer about appetite suppression being the intended effect, not a side effect.

Does stress make GLP-1 side effects worse?

Gerard suggests these effects "show up when life gets busy," but there's no clinical evidence supporting this timing claim. The major trials don't stratify side effects by stress levels or life circumstances.

What we do know is that most GLP-1 side effects peak during dose escalation periods. The STEP 1 trial found nausea peaked at weeks 4-8, then decreased even as people stayed on the medication.

Gerard might be observing that people notice side effects more during stressful periods, but that's different from claiming stress causes or worsens the actual physiological effects of these medications.

What should you actually know about GLP-1 side effects?

The real side effect profile is well-documented and doesn't match Gerard's "little" description. In STEP 1, 74.2% of people experienced gastrointestinal events versus 47.9% on placebo.

The most common issues are nausea (44%), diarrhea (30%), vomiting (24%), and constipation (24%). These aren't minor inconveniences for many people. The STEP 1 trial saw 7% of participants stop treatment due to side effects.

Gerard's heart seems to be in the right place, trying to normalize the GLP-1 experience for his community. But calling documented, sometimes treatment-limiting side effects "little" undersells what people might actually face on these medications.