Is the 0.8 g/kg RDA enough while losing weight?

0.8 g/kg/day is the general reference intake to prevent deficiency in healthy adults — it isn't aimed at preserving muscle during weight loss. Studies link higher intakes (about 1.2–1.6 g/kg/day) to better lean-mass retention while dieting. Confirm your target with your dietitian.

How do I calculate my protein target?

A simple starting point is your body weight in kilograms multiplied by 1.2 to 1.6. For example, a 75 kg person would aim for roughly 90–120 g of protein per day. Your clinician can personalise this.

Can too much protein be a problem?

For most healthy people, higher protein within these ranges is well tolerated. But if you have kidney disease or another medical condition, you should not increase protein without medical advice.

How Much Protein Do You Need on a GLP-1?

Published 30 May 2026Evidence-based · 5 sources

Protein is the single most important nutrient to get right on a GLP-1 medication. Here's how to set a sensible target — and why it matters more during rapid weight loss.

Start with the baseline

The general adult reference intake is about 0.8 g of protein per kilogram of body weight per day, and European reference values land in a similar place at around 0.83 g/kg/day. Those figures are designed to prevent deficiency in healthy adults — they are not optimised for someone losing weight quickly.

Why you likely need more while losing weight

When you lose weight, some of it can come from lean (muscle) tissue as well as fat. Higher protein intakes of roughly 1.2–1.6 g/kg/day are associated with better preservation of lean mass during energy restriction. For older adults, the PROT-AGE expert group recommends at least 1.0–1.2 g/kg/day, and more for those who are active or unwell.

This matters on GLP-1 medications specifically because weight loss can be rapid. In the STEP 1 trial of semaglutide, overall body composition improved (fat fell more than lean mass), but absolute lean mass still decreased — which is exactly why protein, paired with resistance exercise, is so important.

A simple way to set your target

Prefer to skip the math?Calculate your protein target →

Multiply your body weight in kilograms by 1.2 to 1.6:

60 kg → about 72–96 g protein/day
75 kg → about 90–120 g protein/day
90 kg → about 108–144 g protein/day

Spreading protein across meals helps too: the PROT-AGE group suggests roughly 25–30 g per meal for older adults to best support muscle.

Confirm your personal target with your dietitian or doctor — and if you have kidney disease, do not increase protein without medical advice.

Frequently asked questions

Is the 0.8 g/kg RDA enough while losing weight?: 0.8 g/kg/day is the general reference intake to prevent deficiency in healthy adults — it isn't aimed at preserving muscle during weight loss. Studies link higher intakes (about 1.2–1.6 g/kg/day) to better lean-mass retention while dieting. Confirm your target with your dietitian.
How do I calculate my protein target?: A simple starting point is your body weight in kilograms multiplied by 1.2 to 1.6. For example, a 75 kg person would aim for roughly 90–120 g of protein per day. Your clinician can personalise this.
Can too much protein be a problem?: For most healthy people, higher protein within these ranges is well tolerated. But if you have kidney disease or another medical condition, you should not increase protein without medical advice.