There are two reasons you need adequate protein in your diet.  The first reason is to stop hunger.  The second reason is to repair and maintain your lean body mass.   Lean body mass is your weight minus your total body fat.  Lean body mass includes your muscles, your organs, and your bones.

Hunger Suppression
Your level of hunger suppression for the next five hours is determined by the amount of protein in your previous meal.  That amount of protein seems to be invariant for age and sex.  Research suggests that approximately 30 grams of protein per meal is required for successful appetite suppression.  Consuming less than 30 grams of protein per meal will be insufficient to stimulate the release of various hormones (GLP-1, PYY, and GIP) from the gut that go directly to the brain via the vagus nerve to signal satiety. Consuming more than 35 grams of protein at a meal can inhibit AMPK activity.

Maintaining Lean Body Mass
The second reason you need protein is to maintain your lean body mass. Lean body mass is your total weight minus your total body fat. It consists of the weight of your organs (muscle, brain, heart, liver, etc.) and bones. The term “healthy weight loss” is correct if you lose excess body fat without compromising your lean body mass. 

The amount of protein needed to maintain lean body mass is more variable than the level required to stop hunger.  It is dependent on your existing lean body mass, your physical activity level, and your age.  If you are an active athlete doing high levels of physical training, your protein needs to maintain your lean body mass will be different than those of someone of equal age who is sedentary. Surprisingly, if you are older than 65, your protein requirements significantly increase to maintain your lean body mass regardless of physical activity.  This is because the body begins to develop protein resistance.  This means the ability of dietary protein to stimulate new tissue formation is compromised, and you may need additional dietary protein intake.

So, you can see that while protein intake for satiety is constant, the protein intake needed for maintaining lean body mass can be variable. In other words, everyone is different. This is why I developed a unique calculator to estimate your protein requirements at various stages of life.

The Protein Requirement Calculator considers your weight, gender, age, and various measurements. These measurements allow you to determine how much protein you need to consume to maintain lean body mass while losing excess body fat.

Once you determine how much protein you need each day, spread that amount throughout the day in relatively constant amounts. Each meal should contain at least 30 grams of protein but not more than 35 grams. The protein level at a meal determines the amount of carbohydrates and fat you need to maintain the hormonal balance needed to reduce insulin resistance using Metabolic Engineering™. Practically, this means each meal would contain between 400 and 500 calories.


Measuring Body Fat

The Protein Calculator also estimates your percent body fat.  Estimating your body fat percentage is important in monitoring your progress in reducing insulin resistance, as excess body fat drives insulin resistance.

ClassificationWomen (% Fat)Men (% Fat)
Essential Fat10%-13%2%-5%
Healthy levels of body fat21-31%14-24%
Obese32% and above
25% and above

Using BMI as a marker of obesity can be deceiving. Many individuals considered “normal weight” by BMI measurements (i.e.,  a BMI less than 25) are obese based on their percent body fat.