Most people trying to lose weight should aim for 1.2 to 1.6 grams of protein per kilogram of body weight per day. For a 150-pound person, that works out to roughly 82 to 109 grams daily. If you’re also lifting weights or doing intense exercise while cutting calories, you may benefit from going even higher, up to 2.0 grams per kilogram or more.
How to Calculate Your Target
Start by converting your weight to kilograms (divide your weight in pounds by 2.2). Then multiply by the protein range that fits your situation:
- Sedentary or lightly active, losing weight: 1.0 to 1.2 g/kg per day
- Moderately active, losing weight: 1.2 to 1.6 g/kg per day
- Resistance training while cutting calories: 1.6 to 2.4 g/kg per day
A 180-pound person who walks regularly and wants to lose weight would calculate it like this: 180 รท 2.2 = 82 kg, multiplied by 1.2 to 1.6, giving a range of 98 to 131 grams of protein per day. Someone at the same weight who lifts four days a week might push that to 130 to 160 grams or beyond.
For context, the standard recommended daily allowance for protein is just 0.8 g/kg per day, a number designed to prevent deficiency in the general population. Athletes and people actively losing weight need substantially more. Research consistently shows that trained individuals require 50 to 175% more protein than sedentary people.
Why Protein Helps With Weight Loss
Protein burns more calories during digestion than any other macronutrient. Your body uses 20 to 30% of the calories in protein just to process it, compared to 5 to 10% for carbohydrates and 0 to 3% for fat. If you eat 100 calories of protein, your body spends 20 to 30 of those calories on digestion alone. Over the course of a day, swapping some carb or fat calories for protein creates a small but meaningful metabolic advantage.
Protein also changes the hormonal signals that control hunger. After a high-protein meal, your gut releases higher levels of hormones (GLP-1 and PYY) that tell your brain you’re full. These levels stay elevated for hours compared to meals built around fat or carbohydrates. In practical terms, this makes it easier to eat less without feeling deprived, which is the real challenge of any calorie deficit.
What the Weight Loss Data Shows
In a randomized clinical trial comparing high-protein diets to standard-protein diets, people eating more protein lost 7.0 kg (about 15 pounds) over six months, while the standard-protein group lost 5.1 kg (about 11 pounds). That’s a meaningful gap. Among people who stuck closely to their assigned diets, the difference was even larger: the high-protein group lost 9.5% of their body weight versus 5.8% in the standard group.
The advantage isn’t just about the number on the scale. In a study that put young men on a severe calorie deficit (40% below their energy needs) for four weeks, those eating 2.4 g/kg of protein per day actually gained 1.2 kg of lean mass while losing 4.8 kg of fat. The lower-protein group (1.2 g/kg) held onto their muscle but barely, gaining just 0.1 kg of lean mass and losing only 3.5 kg of fat. Both groups exercised intensely, but the higher protein intake made the difference between losing mostly fat and losing a mix of fat and muscle.
Protecting Muscle While Losing Fat
When you eat fewer calories than you burn, your body doesn’t just tap into fat stores. It also breaks down muscle for energy, especially if protein intake is low. Losing muscle slows your metabolism, makes you weaker, and changes your body composition in ways that make regaining weight easier later.
Keeping protein high is the single most effective dietary strategy for preserving muscle during a calorie deficit. For people who do resistance training while dieting, the International Society of Sports Nutrition suggests protein intakes as high as 2.3 to 3.1 g/kg of fat-free mass to maximize muscle retention. That’s a lot of protein, and it’s most relevant for lean, serious lifters. For most people losing weight with moderate exercise, staying in the 1.2 to 1.6 g/kg range provides strong protection against muscle loss.
How to Spread Protein Across the Day
Your body can only use so much protein at once for muscle repair and growth. The current best estimate is about 0.4 g/kg per meal, spread across at least four meals. For a 70 kg (154-pound) person, that’s roughly 28 grams per meal, four times a day, totaling around 112 grams.
If your daily target is higher, you can push each meal to about 0.55 g/kg, which would be around 38 grams per meal for that same person. The key principle is even distribution. Eating 10 grams at breakfast and 80 grams at dinner is less effective for muscle preservation than splitting your intake more evenly throughout the day. A simple approach: include a palm-sized portion of protein-rich food at every meal and snack.
Protein Needs After Age 65
Older adults need more protein per meal to get the same muscle-building response that younger people get from a smaller amount. This is called anabolic resistance, and it means that the standard 0.8 g/kg recommendation is particularly inadequate for anyone over 65.
Experts in protein and aging recommend 1.2 to 2.0 g/kg per day for older adults, even before factoring in weight loss goals. The per-meal threshold for stimulating muscle repair is about 0.24 g/kg in older adults, roughly 70% higher than what younger adults need. For a 70 kg older adult, that means aiming for at least 17 grams of protein per meal rather than the 10 to 12 grams that might suffice for someone in their 20s. Since age-related muscle loss (sarcopenia) is one of the biggest threats to independence and mobility, maintaining high protein intake during weight loss becomes especially important later in life.
Is High Protein Safe for Your Kidneys?
This is the most common concern people have about eating more protein, and the answer depends on whether your kidneys are already healthy. Randomized trials lasting six months or longer have generally shown little to no effect of high-protein diets on kidney function in people with healthy kidneys. However, high protein intake does increase the workload on your kidneys by raising filtration pressure, and there is some evidence that this could be problematic over very long periods or for people who already have reduced kidney function.
If you have existing kidney disease or are at high risk for it (due to diabetes or high blood pressure, for example), pushing protein well above 1.2 g/kg per day without medical guidance is not a good idea. For everyone else, intakes in the 1.2 to 2.0 g/kg range are well within the boundaries that clinical research has studied without finding harm. Staying hydrated and getting protein from a variety of sources (rather than relying solely on red meat or supplements) is a sensible baseline practice.