Fad diets often put a certain food in the spotlight to convince you that it has magical weight loss properties. The common banana, an inexpensive staple fruit, has had its fair share of promotional time. Fad diets pair bananas with milk -- and more contemporary banana-based fad diets let you eat as many calories as you want. A bananas-only diet, or any diet that focuses on one type of food, is an unhealthy way to lose weight.
Bananas and Fad Diets
One fad dating back to the late 1920s is Dr. George Harrop's diet, which consists of skim milk and bananas only. A more recent fad diet made its way to the United States from Japan, where it first gained notoriety. Information from the American Dietetic Association indicates that the Morning Banana Diet lets you eat a banana for breakfast and as much as you want for lunch and dinner. This banana-based diet imposes other quirky rules; meals must be accompanied by room-temperature water, and you cannot eat past the hour of 8 p.m. There's no magic fruit, vegetable or other food that makes you lose weight. Weight loss is dependent on one thing: consuming fewer calories per day than your body burns.
Bananas do impart some essential nutrients needed for a healthy diet. One medium banana gives you around 110 calories with no fat, sodium or cholesterol. A banana also gives you 10 percent of your daily value, or DV, based on a 2,000-calorie diet, as well as 35 percent of your DV for vitamin B6, 20 percent of your DV for vitamin C and 10 percent of your DV for magnesium. Because the number of calories you consume is ultimately the deciding factor in weight loss, you'd have to get fewer calories than you normally eat on a bananas only diet. If you ate 20 bananas a day, you'd get more than 2,000 calories from this fruit alone. If you consumed 15 bananas and drank three glasses of skim milk -- which gives you another 360 calories -- you'd also get more than 2,000 calories a day.
A bananas-only diet is just as impracticable as other diets that focus on eating one specific food or combination of foods or fad diets that eliminate specific food groups. According to the ADA, you'll likely have shortages in certain nutrients, even if you take a daily multivitamin. Avoid these diets, especially if you hear that you'll lose a lot of weight in a short period of time on the diet. You may or may not lose weight on a fad diet, but if you do lose weight quickly by eating bananas -- or cabbage or grapefruit -- it's impossible to sustain for a lifetime. To keep your weight right where you want it, it's essential to keep the number of calories you eat and the number of calories you burn in balance. Weight loss should also happen slowly and steadily. The ADA recommends losing 1/2 to 1 lb. a week; MayoClinic.com, on the other hand, notes that 1 to 2 lbs. a week is acceptable.
Reduced Calorie Dieting
Calorie reduction plays a key role in weight loss, as does a healthy diet. A healthy diet includes foods from all of the food groups and emphasizes eating fruits, vegetables, whole grain foods, low- and nonfat dairy foods, lean proteins, nuts and seeds. MayoClinic.com notes that you should still be able to have your favorite sweet every now and then. Harvard Medical School suggests cutting your daily diet by 500 calories and getting at least 30 minutes of physical activity every day to lose a pound a week. However, don't crash diet; this could put good nutrition at risk, not to mention your health. Women should get at least 1,200 calories a day; men need at least 1,500.