If your diet is bad and exercise routine is good there will be no loss. The reason diets don't work is because diet and exercise must go together. What food and exercise combo works best?

Diets and exercise do not have to go together. You can be a quadraplegic and burn fat because most of the calories an average person expends come from basal metabolic processes. Check out these fitness facts.
??? If you consume fewer calories than you burn, you have to lose fat eventually. There are no exceptions to this fact.
??? There are only two nonsurgical things you can do to sculpt your body and they are (1) add or lose fat and (2) add or lose muscle. Muscle can only be lost naturally through atrophy.
??? A pound of fat will yield about 3500 calories (Kcal) of energy.
??? An average person must run or walk about 5 miles (8 km) every day to burn one pound of fat per week BUT THEIR DIET MUST ALLOW IT.
??? An average person must run or walk about 350 miles (563 km) to burn 10 pounds BUT THEIR DIET MUST ALLOW IT. If they walk 350 miles (13.4 marathons) at 3mph it will take them 117 hours or about three full 40 hour work weeks to burn 10 pounds of fat.
??? If an average person consumes 500 calories per day less than they burn, they will lose about a pound a week with no extra time or physical effort required.
???Running does not burn any more fat than walking as long as the distance remains the same.
??? It does not matter if a person runs or walks a given distance???they will burn the same number of calories. Calories are energy and energy expenditure is not time dependent. How fast a person runs has nothing to do with how many calories they burn. Only the distance determines the calories burned.
??? It is not necessary to do "cardio" to burn fat. Cardio is aerobic exercise while maintaining a heart rate of 80% of max or more which is used to maintain cardio-vascular fitness. You can burn fat in your sleep.
??? Most of the calories you consume will be spent just keeping your body temperature at 98.6F.
??? It doesn???t matter how hard or how long you exercise, you will not lose any fat if you eat too much. You can always eat more calories than you can burn. When it comes to burning fat, diet always trumps exercise.
??? There are no supplements which will make your body burn fat. Only you can do that with diet control.
The best diet for losing fat is the same as the best diet for building muscle which is the same as the best diet for maintaining health and body weight. In other words, everyone should be eating essentailly the same macronutrients, vitamins, minerals, and fiber barring special health or medical considerations because we all have essentially the same physiognomy. Here is the diet approved by the US National Institute of Health...the people your doctor listens to.
Eat varied, wholesome, and high quality foods such that your daily caloric intake is about equal to your daily caloric burn while keeping your macronutrient ratios at about 55/25/20 (%calories from carbs/fats/protein). Only slight changes should be made in the macronutrient ratios to accommodate the extreme demands of special activities such as athletics or inactivity due to illness.
Note: Here are the details in case you're interested. ---> http://health.gov/dietaryguidelines/2010???
and here ---> http://www.nlm.nih.gov/medlineplus/nutri???
You get to make the food choices based on culture, available foods, personal preferences, your resources, etc. However, the words "varied", "wholesome", and "high quality" are important. And, you should consume your food in 4-6 daily meals with healthy snacks between such that you're nourishing yourself every two hours when awake.
If you want to burn body fat, simply decrease portion sizes of your food such that your daily intake is 500 calories less than your daily burn rate. That should result in a loss rate of one pound per week or 30 pounds in 30 weeks lost safely.
What diet and exercise combination works best depends on what you mean by "best" and/or the individual and their metabolism, fitness goals, resources, etc.
There is no one best diet and exercise combo for all people.
Good luck and good health!!
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