We recently went to a restaurant with friends. One of them brought along an acquaintance. This acquaintance, Julie, posed some special questions to the waitress, asking that everything be prepared without eggs, milk, cheese or butter. She proudly informed us that she recently became a vegan. That means that, not only does she not eat poor animals, she also categorically refuses any kind of animal product.

We asked her where this unexpected pity for beasts had come from; just a couple of months ago, we all happily ate steaks together, and there were no tears on her cheeks then. Julie, a real American — plump, but with a thin and very attractive face — said that she wanted to lose weight. Well, who among us sitting at that table was going to say that a large pizza without cheese and a generous helping of lemon sorbet could hardly be called an effective diet? Even if no animals suffered for it.

Americans, like all of us, want to live long, healthy lives. But reaching this goal is a little complicated for them: The vast majority of food in the States is harmful, everyone starts to drive at age 16, on every corner there is a McDonald's and around every corner there is a Burger King. Healthy nutrition and an active lifestyle have to be a personal, conscious and not always simple choice that is the result of a daily struggle with habits and temptations.

Getting fat is one of the scariest nightmares for America. It is the cause of many illnesses, including diabetes and heart disease. Heart attacks occur about every 20 seconds in the country, and someone dies of one every minute. For some years, doctors have been sounding the alarm and trying to convince people that a healthy heart is much more important than taking pleasure in such traditional foods as burgers and sandwiches with steak and cheese.

Diets and healthy eating programs are growing, but one of the most popular is still Weight Watchers — a unified system which assigns points to each food eaten and limits the number of points per day. American celebrities appear in advertisements citing the effectiveness of the program, quickly losing weight and sliding into skinny jeans. But dieticians don't much care for Weight Watchers because it allows one to eat anything, just in significantly smaller amounts. The habits and food tastes of the person don't change, and as soon as he stops limiting himself on portions, the weight returns.

The 17-Day Diet is very popular in the States — at my gym, at the beginning of January, there was a group who wanted to try it. I joined out of curiosity. The diet was developed by Dr. Mike Moreno and consists of four cycles of 17 days each. The idea is that the diet constantly changes, so the body cannot adapt to it. The metabolism speeds up and kilograms of weight come off. The first cycle excludes practically all the joys of life: Carbohydrates are forbidden, including even some vegetables like potatoes and eggplant, as well as sugar, red meat, alcohol and grains. One can have non-fat yogurt and kefir, chicken and turkey, fish, as many vegetables as desired, two portions of fruit or berries per day, a lot of water and green tea. The next 17 days, the diet adds carbohydrates, beef and seafood, and the one after that — all the rest of the forbidden goodies. The fourth cycle, ideally, should last a lifetime. After a person re-learns how to measure portions, to eat fruits and take vitamins every day, the diet teaches one to eat "correctly" five days per week, and on weekends one is allowed a couple of favorite dishes and a glass of wine with dessert.

All of that would probably not be so interesting to me, if the diet at our gym was not supported by Tammy Smith — a certified nutrition specialist. At our weekly meetings she talked about bad and good fats, cholesterol, the damage caused by sugar and the so-called "white carbohydrates." As a result of these three months I once again began to cook seriously — first after a meeting with Steve (who feels like cooking if their husband is a chef?). Well, as a result I became a real pest and am able to talk for hours about healthy food with the enthusiasm of a Jehovah's Witness. Finally, my husband got tired of grumbling about organic radishes and began reading labels on his own and bringing home bread made from sprouted seeds instead of donuts.

I would very much like to know what my blood type is. Somehow it happened that over the course of my whole life, I have never found this out. As it turns out, many doctors believe that if one eats in accordance with one's blood type, life will improve, the body will be healthier and stronger, and one will just burst with energy. Every blood type has recommended foods, neutral foods which cause no harm but are also not useful, and foods from which they should abstain. Thus, a person in the first group needs to eat meat and fish, but shouldn't eat wheat or ketchup. The second group is destined to be vegetarians; beans and pineapple are especially good for them. The third group is advised to avoid seafood, and the fourth group loves meat. My Danish yoga instructor, Pernilla, who at 46 could pass for 31, said that she was a vegetarian for 15 years on moral grounds and out of a desire to be healthier. She always felt bad after eating, and her energy was low even after yoga classes. Then she realized that she belonged to the fourth blood type and needed to eat meat. She made a deliberate, radical change to her diet. Pernilla recognized that despite her pangs of conscience, she had never felt better.

Yet another new diet is Ideal Protein. All the well-heeled “office plankton” [a Russian slang term which has made its way into English; it refers to low-level office workers, clerks, etc.] are on it. Practically all of the food has to be bought from the program founders, and it is basically powder that one dissolves in water. The idea is to feed the body small portions of ideal protein, to exclude carbohydrates and sugar, and to quickly lose weight. One must not engage in sports while on this diet, otherwise one will lose muscle mass and not just fat from one's belly. It sounds pretty simple but this program costs almost a thousand dollars. As one of my friends said, "if you want to be hungry, I will send you a hunger strike for free."

One of the most interesting new diets could be called the Paleo diet, one that is not so much a diet as a way of life. Its followers believe that people of the Paleolithic period knew better than we do what to put on their plates (or bamboo leaves). The first people conducted an active lifestyle, jumping around in trees and eating simple and healthy food. The Paleo diet does not recognize any grains or processed foods, dairy products, sugar, or even honey. Hunter-gatherers, in the opinion of the Americans, ate meat, fish, fowl, fruits and vegetables, nuts and roots. It seems that there is little variety, but nevertheless, Paleo-cooks prepare excellent cakes of coconut flour and ice cream from bananas.

For some reason, followers of the Paleo diet often engage in cross-fitness, an intensive training program consisting of a series of many varying exercises for strength and speed. Maybe that gives them the opportunity to burn as many calories as Stone Age people must have burnt on mammoth hunts. Or, much simpler: When one is drawn into difficult and demanding classes that demand all of one’s energy, one does not want to spoil their effects with a bad diet. The understanding quickly comes that the body reacts sensitively to everything that they feed it. I understood this when I began to notice my progress in hot yoga after a few weeks on the 17-Day Diet. We are what we eat, after all.

All of these diets, in fact, pursue simple goals and follow very similar paths: limit portions; vary the diet; add more vegetables and fruits; cut out or limit sugar, carbohydrates and alcohol; eat simple and healthy food, grown locally and in season; seek organic, clean vegetables and fruits; abstain from processed foods containing genetically modified ingredients.

Dieticians reassure Americans: Don't spend two weeks on a diet, as that doesn't help. Make it a part of your life, eat correctly 80 percent of the time and then the other 20 percent of the time you can let yourself have some unhealthy treats. Incidentally, the newest diet is called the 5:2. Its principle is that a person eats according to his habits, but twice a week he cuts his intake to 500 calories per day. Hallelujah! The Americans have finally discovered the fasting day!