W eight loss isn't only -- or even mainly -- about calories. Surprisingly, we gain weight when natural weight-control mechanisms are disrupted by inflammation, a low-grade inflammatory response caused by poor diet and environmental toxins.

When people gain weight, the extra fatty tissue produces leptin, a hormone that suppresses appetite and speeds metabolism. In theory, this should cause people to lose the extra weight.

Instead, inflammation in fat tissue and blood vessels stimulates the production of anti-inflammatory chemicals. These chemicals disable leptin's ability to suppress appetite and speed metabolism. This is called leptin resistance.

To combat leptin resistance, I have developed a fat-resistance diet based on cutting-edge research at premier institutions such as Harvard, Johns Hopkins and Rockefeller universities. Eating the proper foods can eliminate chronic inflammation and reprogram the body's weight-loss mechanisms.

Anti-Inflammatory Foods

The focus of the diet isn't calorie control. The idea is to eat foods that supply anti-inflammatory nutrients. A major problem with most weight-loss diets is the use of artificial sweeteners and fat substitutes to reduce calories. Substituting these products for real foods deprives your body of key anti-inflammatory nutrients. Main principles...

Eat fish at least three times weekly. The omega-3 fatty acids in fish have powerful anti-inflammatory properties. Fish that are rich in omega-3s and relatively low in mercury include anchovies, conch, herring (fresh or pickled, not creamed), mackerel (Atlantic only), sablefish, salmon (fresh, canned or smoked, wild or farmed), sardines (Atlantic), sturgeon and tuna (fresh or canned bluefin -- not albacore).

Balance essential fatty acids. The optimal ratio of omega-6 fatty acids to omega-3s is about 4:1. The ratio in the average American diet is closer to 20:1. A relative excess of omega-6 fats in tissues leads cells to produce excessive levels of pro-inflammatory chemicals called prostanoids. The best approach is to decrease intake of omega-6s and increase intake of omega-3s. Foods high in omega-3s: Fish, flaxseed, walnuts and beans—navy, kidney and soybeans. Foods high in omega-6s: Red meat, chicken, milk, eggs and most vegetable oils, including corn, sunflower and safflower.

Cut back on unhealthy fats. Saturated fat -- primarily found in beef, pork, lamb, dairy products and poultry skin -- should be limited to no more than 10% of total calories. Don't eat any trans fat -- this means avoiding any foods made with hydrogenated or partially hydrogenated vegetable oil. These include most commercial baked goods and some fast foods. Both saturated fat and trans fat greatly increase levels of inflammatory chemicals.

Get 25 grams of fiber daily. A high-fiber diet helps control appetite and reduce inflammation. A study by the Centers for Disease Control and Prevention found that people who consume the most fiber have lower levels of C-reactive protein (CRP), which indicates the presence of inflammatory chemicals in the body. All plant foods contain some fiber. Among the best sources are beans, whole grains and vegetables.

Eat colorful fruits and vegetables. Get at least nine servings daily. Produce with deep colors and intense flavors is high in flavonoids and carotenoids, chemical compounds that have anti-inflammatory effects.

Important: Have at least one serving of blueberries, cherries or pomegranates a day. These contain anthocyanins, which are among the most potent anti-inflammatory agents.

Choose alliums and crucifers. Crucifers are strong-flavored vegetables, including broccoli, cauliflower, cabbage and kale. Alliums include onions and garlic. Both classes of vegetables reduce chronic inflammation and lower the risk of cancer, particularly breast cancer. Eat at least one serving of each daily.

Use only egg whites or unbroken egg yolks. The cholesterol in yolks has relatively little effect on cholesterol in the blood -- but if the yolk is broken, the cholesterol is oxidized and produces inflammatory by-products. Poached or boiled whole eggs are fine. Avoid scrambled eggs and whole-egg omelettes.

Favor herbs and spices that are potent anti-inflammatories. These include basil, cardamom, cilantro, cinnamon, clove, ginger, parsley and turmeric. Use them every day. Avoid chiles, cayenne pepper and jalapeños, which can trigger inflammation.

THREE STAGES

The diet progresses in phases...

Stage 1. Eat as much as you want of such foods as arugula, bell peppers, broccoli, cabbage, carrots, leeks, onions, romaine lettuce, scallions, shiitake mushrooms, spinach and tomatoes -- as well as blueberries, cherries, grapefruit and pomegranates.

Eating three four-ounce servings of high-protein foods each day helps suppress appetite and maintain muscle mass. Choose fish, egg whites, poultry and plain, fat-free yogurt. Meat lovers can eat red meat twice a week but should marinate beef with cherry or pomegranate concentrate (this reduces inflammatory chemical compounds produced during cooking). You can have a tablespoon or two each day of nuts or seeds (especially flaxseed, walnuts and almonds). During this stage, get 25 grams of fiber, primarily from vegetables.

Avoid grains, even whole grains, because they tend to raise insulin levels, increasing leptin resistance.

Most people stay in this stage for two weeks and lose six to 10 pounds.

Stage 2 is the long-term weight-loss part of the diet. Stay on this until you reach your goal weight. Expect to lose one to two pounds per week.

In addition to the Stage 1 foods, add some whole grains, such as oats and brown rice, and beans, lentils and other legumes (about two to three cups a week of each).

Stage 3 is the lifelong maintenance phase. Increase variety by adding potatoes, pasta and whole-grain breads.