The Paleo Diet - Loren Cordain [54]
In order to get enough protein and calories, you should eat animal food at almost every meal. You can’t just eat animal food, however. You must eat fruits and vegetables, too. Here’s why: if protein-dense, extremely lean meats and seafood are your main sources of calories, you will get sick—with nausea, diarrhea, and weakness—because your body can’t handle this much undiluted protein without something else, either fat or carbohydrates. As we discussed earlier, early Arctic explorers, trappers, and frontiersmen who had no choice but to eat the fat-depleted meat of game animals in the dregs of winter rapidly developed these same symptoms, frequently referred to as “rabbit starvation” or protein toxicity.
The problem, as shown in Dr. Daniel Rudman’s laboratory at Emory University in Atlanta, is that the liver can’t effectively eliminate the nitrogen caused by the protein overload. For most people, the dietary protein ceiling is 200 to 300 grams a day, or about 30 to 40 percent of the normal daily caloric intake.
On the other hand, eating too many fatty meats can wipe out any health benefits that eating high levels of protein will help you achieve. Paleolithic people couldn’t eat fatty meats if they tried—they had nothing like the tubby grain-fed animals that produce our steaks today. Wild game meat contains about 15 to 20 percent of its calories as fat. A lean cut of beef trimmed of all visible fat contains more than double this amount (35 to 40 percent fat). And certain fatty cuts of meats may contain 65 to 80 percent fat.
FAT AND PROTEIN CONTENT (PERCENTAGE OF TOTAL CALORIES OF MEAT AND FISH)
Not only is the total amount of fat higher in commonly consumed fatty meats—such as hamburger, T-bone steak, hot dogs, and lamb chops—than that found in fish and game meat, but the types of fat are also quite different. Because most commercially available beef has been feedlot-fattened (mainly with corn and sorghum), it contains low levels of omega 3 fats and high levels of omega 6 fats. This is the wrong mix. When eaten in excess, omega 6 fats are harmful, while omega 3 fats are greatly beneficial. The average Western diet is burdened by high levels of omega 6 fats—which can promote the development of heart disease in many ways. The meats, fish, and seafood you’ll be eating on the Paleo Diet are low in fat and high in protein, and they contain the correct balance of omega 3 and omega 6 fats.
What about eggs? Eggs are a relatively high-fat food (62 percent fat, 34 percent protein). Eating too many eggs can promote weight gain and increase blood cholesterol levels. There is no doubt that Paleolithic people would have eaten wild bird eggs whenever they found them. But this wasn’t that often. Wild eggs always would have been a seasonal food and would not have been eaten every day. Also, wild bird eggs are nutritionally different from domesticated chicken eggs; they have higher levels of beneficial omega 3 fat and lower levels of certain saturated fats. You should also buy eggs enriched with omega 3 fats.
The high protein of the Paleo Diet is the key to many of its weight-loss benefits. Protein helps you lose weight faster by boosting your metabolism while simultaneously blunting your hunger. And while this is happening, low-fat protein is improving your blood lipid and cholesterol levels, as studies from Dr. Bernard Wolfe’s laboratory at the University of Western Ontario have confirmed. Low-fat protein also prevents blood sugar swings and reduces the risk of hypertension, stroke, heart disease, and certain cancers.
Salmon for breakfast? Breakfast is one part of the Paleo Diet that may seem a bit strange at first. In Western countries, breakfast is usually a high-carbohydrate affair,