This handy calculator is great as a guide, and should always be used in conjunction with your dietitian and doctor.

​

Context and information:

GLP-1 receptor agonists such as semaglutide, liraglutide and tirzepatide can lead to significant weight loss, but an estimated 25-40% of that loss may come from lean mass, which can increase the risk of sarcopenia, functional decline and poorer glycaemic outcomes.

 

Because these medicines often reduce appetite and total energy intake, a patient's absolute protein intake may fall below the amount needed to support their muscles, particularly for older adults and people with anabolic resistance. A joint advisory from the ACLM, ASN, OMA and TOS recommend that the patient aim for 1.2-1.6 g/kg/day of protein (based on adjusted body weight) during active weight reduction, alongside structured resistance training. Protein on its own is not enough to protect lean mass, and aerobic-only exercise appears to offer less protection, so strength-based movement is an important part of the picture. It is worth exploring what types of movement feel safe, accessible and enjoyable for the patient, as sensory needs, energy levels, pain, body image and past experiences with exercise or health care may all shape what is sustainable.

 

Protein quality and distribution also matter prioritising high-quality protein foods, which also supply iron, B12, zinc and calcium, and spreading intake across meals can help support muscle protein synthesis. Because appetite, taste, texture preferences, access to food and eating routines vary between people, these goals are best set collaboratively with you, your GP, dietitian, and other specialists using flexible, non-judgemental approaches that respect their autonomy, culture, food preferences and lived experience.