In recent years, researchers have amassed more and more evidence that what we eat plays a huge role in how disease free we remain. “Along with avoiding tobacco and being physically active, a healthy diet reduces the risk of most major chronic conditions by as much as 80 percent,” says David Katz, MD, director of the Yale University Prevention Research Center. But while doctors can prescribe a great, one-menu-fits-all eating plan for general good health, it’s also possible to tailor your diet to specific health concerns, such as preventing breast cancer, heart disease and irritable bowel syndrome, as well as chronic diseases in general.

Here are four different paths to a healthier you. But before you take action, make sure you get the OK from your physician.

The Intermittent Diet

Goal: Prevent breast cancer

In brief | Severe calorie restriction for two days a week; a Mediterranean diet the other days.

Rationale 

Women who are worried about breast cancer can’t change most of their risk factors, such as their family history, but they can significantly boost their odds of dodging the disease by staying at a healthy weight. Gaining too many pounds after menopause increases breast cancer risk by 30 to 60 percent. This plan is aimed at women who need to lose weight but find it tough to slash calories day after day; here, you have to muster major discipline for only 48 hours a week.

Details

For five days, you follow a Mediterranean-based diet, filled with vegetables, legumes, lean protein and good fats like olive oil. (See here for menu ideas.) You eat the number of calories you normally do when you’re not putting on weight. (In other words, you follow a maintenance diet.) On the two other (not necessarily consecutive) days, you become super strict and consume a maximum of 650 calories, mostly from milk and produce. Are these intermittent low-calorie days dangerous? No, says Katz, although he believes a traditional eating plan might be easier to follow for the long term.

The Evidence 

In a four-month study of 115 women, intermittent dieters shed more weight and body fat and improved their insulin response more than those on a consistent 1,500--calories-per-day Mediterranean diet (the two dieting groups ate the same total number of calories per week). 

For more information and menu plans click here.

A (strict) day on the diet

Breakfast

1 cup black coffee (or add milk from your lunch allotment)

1 banana

Snack

1 cup green tea

Lunch

Cream of carrot soupmade with
2 carrots, 1 vegetable bouillon cube, 1 cup 2% milk and spices of your choice

1 cup skim milk

Snack

1 glass plain sparkling water

Dinner

2 small vegetable portions(a portion equals 2 broccoli spears, 1 tomato or a cereal bowl of either lettuce or spinach) stir-fried with soy sauce and ginger

1 glass water

  Snack

2 cups 1% milkblended with ice to make a smoothie (or served hot with cinnamon and artificial sweetener)

  Diet created by the U.K.’s Genesis Breast Cancer Prevention organization.

The Portfolio Diet

Goal: Cut your risk of heart disease

In brief | Eat food groups known to lower the artery-clogging LDL (“bad”) cholesterol in your blood.

Rationale

Canadian doctors wondered what would happen if they pooled various cholesterol-lowering foods in one eating plan. The resulting Portfolio Diet cuts LDL cholesterol “almost as much as a statin drug” like Lipitor, says plan cocreator Cyril Kendall, MD, PhD, research associate at the University of Toronto. This means you can achieve a clinically significant reduction in your cholesterol without chancing the well-documented side effects of statins, such as muscle aches and brain fog.

Details 

Are you a fan of almonds? The eggplant dip baba ghanoush? Tofu stir-fry? These are the kinds of foods you eat more of on the Portfolio Diet. The plan calls for adding a variety of foods to your daily menu: 42 grams nuts; 15 grams soluble fiber (found in carbs such as beans, eggplant, okra, barley, flaxseed and oats, as well as the psyllium husks sold in health food stores); 25 grams soy proteins (you’ll need four servings of tofu, soy milk, soy yogurt, soy burgers and edamame); and 2 grams plant-sterol oils, which are used as a food additive in spreads such as Promise Activ.

The Evidence

People with high cholesterol who followed the Portfolio Diet for six months saw a drop in LDL levels of 13 percent, compared with a 3 percent decline for those on a conventional low-saturated-fat plan, according to a study reported last year in the Journal of the American Medical Association. (A very high dose of statins can lower your cholesterol by 50 percent, and a low dose by 18 to 25 percent, so this diet best suits people with mildly to moderately high cholesterol.) In a sign of further protection against heart disease, Portfolio Diet followers also experienced a decline in blood pressure and triglycerides.

For more information and menu plans click here.

A day on the diet

  Breakfast

1 cup oatmeal sprinkled with ½ cup strawberriesand 1 tablespoon ground flaxseed

  Snack

1 orangeand 23 almonds or other tree nuts

  Lunch

Salad of lettuce, tomatoesand peppers, topped with 5 olives, 1 ounce feta cheeseand 1 to 2 tablespoons Greek dressing

Handful of carrot sticksor pita chipsdipped in ¼ cup hummus

  Snack

1 pear

½ cup edamame

  Dinner

1 soy burgerwith lettuceand tomatoon a bunspread with 1 to 2 tablespoons plant-sterol margarine

½ cup baked beans

  Snack

Berry-banana smoothie, made by blending 1 cup soy milk, ½ banana, 1 cup berries, ½ teaspoon psylliumand ice

One-day plan created for Moreby Kathleen Humbert, RD, a clinical dietitian in the lipid and prevention program at the Virginia Mason Medical Center in Seattle.

The Core Food Plan

Goal: Reduce your risk of chronic disease

In brief | Vegetables reign supreme.

Rationale 

A group of doctors and dietitians at the Institute for Functional Medicine (IFM) wanted to create a diet plan that spells out for Americans which foods are best, when they should be eaten and in what combinations. “We believe the government’s latest recommendations overemphasize dairy products and starchy foods,” says Elizabeth W. Boham, MD, RD, a physician and dietitian at the UltraWellness Center in Lenox, Massachusetts. (Starchy foods include white rice, potatoes and bread; these boost blood sugar quickly.) So IFM developed the Core Food Plan, which combines healthful options, including low--glycemic foods (these maintain even blood sugar levels, which help prevent type 2 diabetes); a balance of soluble and insoluble fiber (providing possible protection against cancer); a ton of micronutrients known as phytochemicals (ditto); and adequate potassium (reducing risk of high blood pressure).

Details 

Plan the bulk of your meals around veggies “because you get many more vitamins, minerals and phytochemicals per calorie here than from any other foods out there,” explains Boham, who helped develop the program. Toss them into morning omelets, have vegetable soups or salads with lunch and make sure veggies are on your dinner menu. Your goal: four or more daily half-cup (cooked) servings of nonstarchy veggies (such as green broccoli, collards, red peppers and purple eggplants); another two of highly colored starchy veggies (e.g., sweet potatoes rather than white ones; the pigment means you’re getting phytochemicals); plus two of fruits.

The Evidence 

The plan was created after a careful review of major dietary health studies, says Mary Willis, a registered dietitian in Overland Park, Kansas, who helped develop it.

For more information and menu plans go to more.com/corediet.

A day on the diet

*Drink purified water throughout the day.

Breakfast

Omelet made with 2 eggs, 1 ounce smoked salmonand ½ cup spinach

1 cup blueberries

1 cup rooibos herbal tea(a red tea from the legume family) mixed with rice milk

Snack

1 cup sliced yellow pepper stripsand 1 cup jicama sticksdipped in ¼ cup hummus

Lunch

Chicken saladmade by combining 2 cups baby spinach leavesor mixed greens, 3 ounces grilled or baked chicken breast, 1 cup black beansand 12 to 15 crumbled blue corn tortilla chips, and dressed with ¼ cup salsa and 1 tablespoon olive oil–based dressing

Snack

1 small apple

¼ cup almonds

1 cup 1% kefir yogurt drink

Dinner

3 ounces grilled salmondrizzled with 2 teaspoons sesame oil

1/3 cup quinoamixed with ½ cup baked sweet potato cubes

1 cup steamed broccolimixed with 1 tablespoon pesto

6 ounces low-fat blueberry Greek yogurt (for dessert)

This meal plan was created by Mary Willis.

The FODMAP Diet

Goal: Reverse Irritable Bowel Syndrome

In brief | Cut out sugars that may cause distress in the lower digestive tract.

Rationale 

An estimated one in six Americans—the majority of them women—suffer from irritable bowel syndrome, an often poorly managed condition that can combine abdominal pain, gas, bloating, constipation and diarrhea. Now an Australian dietitian, Sue Shepherd, PhD, has developed a healing diet sparked by the observation that people with IBS seem to have trouble digesting certain sugars in their small intestine; foods containing them can bring on uncomfortable gastrointestinal symptoms. Along with Australian colleagues, Shepherd, of LaTrobe University in Melbourne, developed a process-of-elimination plan that allows IBS sufferers to find exactly what causes them problems.

Details

FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols, the chemical structures of potentially problematic sugars. The IBS diet starts by eliminating all of these sugars for about two weeks, then reintroduces foods from one group every seven days to see if they make the IBS sufferer ill. The sugar groups include foods high in lactose (most dairy), fructose (fruits like apples, along with high fructose corn syrup), fructans (wheat, vegetables like onions, and the fiber inulin, which is added to processed foods), galactans (cabbage, beans and tofu) and polyols (plums, nectarines and apricots). When the groups are added back, many people find they can safely eat some of them, especially in small amounts, says Sandy Livingston, a registered dietitian in Palm Beach Gardens, Florida.

The Evidence 

In a recent small British study, 76 percent of IBS sufferers reported significant improvement on the diet, compared with 54 percent of those following standard IBS-diet advice. One concern about following this diet in the U.S. is that none of the FODMAP studies have been done here, so the foods tested are somewhat different from those found in this country. Nonetheless, gastroenterologist William D. Chey, director of the Gastrointestinal Physiology Laboratory at the University of Michigan Health System, has found that some of his patients on the diet could stop their medication.

For more information and menu plans click here. You may also want to consult the book IBS—Free at Last! by Patsy Catsos, which contains advice about the process-of-elimination diet.

A day on the diet (here we’re just eliminating, not adding back)

Breakfast

1 cup unsweetened toasted-oat cerealwith ½ cup blueberries and 1 cup lactose-free low-fat milk

Lunch

4 ounces turkey burgeron a gluten-free hamburger buntopped with ketchup sweetened with cane sugar (such as Simply Heinz Ketchup)

Baked sweet potato fries made from 1 small potato and olive oil spray

1 cup carrotand celery sticks

Snack

2 rice cakesspread with a thin layer of peanut butter

Dinner

Salad of 1 cup mixed greens,tomatoes and olives with dressingof 1 tablespoon each olive oiland vinegar, plus 4 ounces baked white fish like snapper or tilapia with 2⁄3 cup brown riceand ½ cup sautéed baby spinach

Snack

½ ounce mixed nuts

½ grapefruit

Sandy Livingston developed our one-day sample plan.

Next: (Almost) Everything You Know About Saturated Fat Is Wrong

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