Macronutrient ratios refer to percentages of calories taken by mouth. The three macronutrients are carbohydrates (carbs), protein and fat. Calories are different from food-by-weight-in-grams since fat contains 9 calories per gram, protein 4 calories per gram, and carbs, 4 calories per gram. That is why fat is such a good storage vehicle. It is more than twice as dense in energy as carbohydrates, the other principal energy source after carbs.
For a baseline reference, I will use the Standard American Diet (SAD), conveniently reflected on the HHS/USDA’s “Nutrition Facts” panel on processed food packages. Macronutrient ratios there are based on a 2,000 calorie a day diet for women, what women-of-a-certain-age need to maintain their weight. The men’s baseline is 2,500 calories.
The “% Daily Value” (formerly RDA) is based on the HHS/USDA recommendation for women to eat 300 grams of carbohydrates a day (men 375). That’s 1200 calories (300 x 4) or 60% of 2,000 calories diet. Surprised? I’ll bet you are. The protein recommendation is 50 grams for women (62.5 for men), which is 200 calories (50 x 4) or 10% of 2,000 calories. The fat recommendation is +/-67 grams or 600 calories (67 x 9) which is 30% of 2,000 calories. 1200 + 200 + 600 = 2,000. For men, the calories count is 1,500kc carbs + 250kc protein + 750kc fat = 2,500kc total.
This reference standard is very high carb, low protein, low-to-moderate fat. Although the government hasn’t revised the Nutrition Facts standards, they appear recently to be lowering the carb percentage a little (without explicitly saying so), but they also still want you to lower your intake of saturated fat and cholesterol.
So, they now refer to fat simply as oils, by which they mean processed vegetable oils (corn, soybean, sunflower, safflower, Canola, etc.). It is these specific polyunsaturated oils that I and like-minded thinkers are recommending be completely avoided due to instability. My cooking fat preferences are coconut oil, butter, ghee, tallow and lard (think bacon fat) – all saturated fats – and olive oil, a monounsaturated fat, for non-cooking use.
As a further reference, in actual practice surveys show that American men eat 16% of calories from protein, and women 15%. Most nutrition experts recommend people eat no more than 30% of calories from protein, and then only when eaten with fat, and then only when blood tests show no evidence of kidney disease.
What then are the other ranges of macronutrients? What, for example, is considered low-carb? There is no definitive percentage but many people now consider 50 to 100 grams/day to be low-carb (vs. 300 and 375g in the SAD). Fifty grams is 200 calories or 10% of a 2000 calorie diet. 100g is 20%. That’s much better than 300g and a sure way to lose weight. Very Low Carb would be less than 50g/day. Personally, I eat about 15g/day but only 1200 calories total, so 15 x 4 = 60 calories which is only 5% of 1200. There is no minimum dietary requirement for carbs.
On a typical day, I eat 5g of carbs with breakfast, zero grams at lunch, and 10g with supper. If I skip supper, I really lose weight. When I eat almost all fat and protein in this way, my body is keto-adapted, and I don’t get hungry.
That’s where calorie restriction comes into play. If you seriously restrict calories and eat a “balanced diet” of carbs, protein and fat, you WILL feel starved because your body IS being starved. You have limited the energy taken by mouth and, by eating carbs, you have limited your body’s ability to access the stored fat on your body. Your body “notices” you have access to “quick energy” (carbs), from readily available carbs (fruits and vegetables, which it “thinks” must be “in season”), so it asks for (“craves”) more “sugar” (glucose) by mouth. As long as you are a “sugar burner,” it “reasons,” you don’t need to access the dense fat reserves stored on your body.
The hormone insulin regulates your body’s “thinking.” It is “telling” your fat cells to stay put and wait for the impending famine. Your body “think” it is doing you a big favor. No matter how hard you try, it won’t let you burn your precious fat stores. You’re going to need them later. It’s wants you to survive the winter that never comes….When I eat 5% carbs/20% protein/75%fat (5/20/75), I am fat-adapted and I lose weight without hunger (or needing to exercise to lose weight). How? Because my body has access to and can burn its own fat for energy balance.