life1life1Protein is the macronutrient people under-eat when they cut calories, and the one that does the most to keep muscle while fat comes off. The research on how much is unusually consistent.
A 2018 meta-analysis of 49 trials in the British Journal of Sports Medicine found that the benefit of extra protein for muscle gain with resistance training plateaued at roughly 1.6 grams per kilogram of body weight per day. Many sports nutrition bodies suggest a range of about 1.6 to 2.2 g/kg for people training hard, and higher intakes within that range during a calorie deficit.
In a calorie deficit the body draws on both fat and muscle. Resistance training and adequate protein are the two levers that keep the loss mostly fat. Protein is also the most filling macronutrient per calorie, which helps with the deficit itself.
Studies on muscle protein synthesis suggest the response is higher when protein is spread across three or four meals rather than concentrated in one. The practical version is 25 to 40 grams per meal for most adults.
Any complete protein works: meat, fish, eggs, dairy, soy. Plant-based eaters can reach the same totals with legumes, tofu, tempeh, seitan and a mix of sources across the day.
In LIFE1. Scan a barcode, a label, the plate or a menu and LIFE1 fills in the nutrition panel and scores the meal against your protocol’s protein target. The seven-day plan builds a grocery list you can send to Instacart.
In people with healthy kidneys, trials at intakes up to about 2 g/kg have not shown harm. People with kidney disease are different and should follow their clinician’s advice.
No. Shakes are convenient, not necessary. Whole foods reach the same totals.
The Lean and Lift protocols set protein targets from the goal you choose. The meal scanner shows how each plate lands against them. LIFE1 does not give medical advice.
LIFE1 shows what you measured and what published guidelines say. It does not diagnose, interpret or treat. This page is general information, not medical advice.