There isn’t a negative calorie obviously and all you can have is 0+ but this term of a ‘negative calorie food’ just refers to having less calories that you will consume than that you burn from swallowing and digesting the food. Water and diet soda are two examples of drinks that follow this criteria and carrots and broccoli would be two examples of foods that follow this criteria. It is usually fruits or vegetables that are in this category but there are some other foods that fit in it as well.
To help you burn calories even quicker, you could have an ice cold cup filled with water because this will make your blood temperature lower and your body burns energy (calories) bringing it up after you drink the water. Therefore, you can agree that adding ice cubes in your water is a little but helpful method of working towards a weight loss. With negative calorie foods though, there are not that many different foods that fit under this category. You also have to understand that you can’t live on a diet consisting of negative calorie foods because that is very unhealthy and will lead to various health problems – this is the kind of diet that people who are anorexic typically live by or people who generally starve themselves.
You could keep your body filled all day from negative calorie foods but you will be lacking the essential nutrients and vitamins that your body needs every day and no matter how much you want to lose weight, never compromise your current unhealthy life for this because being overweight is by far better than being what this kind of diet would lead to. You could however, use negative calorie foods as a diet for only a few days to quickly lose some weight as a “fast diet” in replacement from not eating for 24-48 hours you just snack on negative calorie foods but anything more than this is not really that healthy.
You will also have to try that you don’t eat a lot of a certain kind of food though because you will probably end up missing certain nutrients that are essential for your daily diet and end up overdosing on certain nutrients that will lead to a health issue. One example of this is that you could get too much acid consumption if you eat too much grapefruits or pineapples and this can end up resulting in you having very strong liver pains or even a case of diarrhea
Eating all day with negative calorie foods can also leave you with a very sore stomach and you will probably feel very ill and bloated. You could create a few negative calorie based meals every single week and slip in the odd negative calorie snack but other than that you don’t want to over consume negative calorie foods.
If you need a full list of negative calorie foods, just do some research (or look at the labels!) but to give you an idea: asparagus, beets, blueberries, broccoli, carrots, cauliflower, celery, cranberries, garlic, green beans, lettuce, onions, spinach, strawberries, tomatoes, turnips, and zucchini are all examples of negative calorie foods.
You will want to make sure that you don’t cause yourself any health issues from consuming these negative calories though as they are meant to be a good addition or alternative for parts of your diet and not your whole diet.