We can’t chemically taste fat, as we taste sour, sweet, salty, bitter and umami (the taste of monosodium glutamate, also known as MSG). And the common meaning of taste goes beyond its chemical definition. That is, how something tastes to us depends partly on how it smells, and on the texture of the food. When answering the question of why fatty foods taste good, we have to look at each of these components.
Smell. Fats help you enjoy the taste of food because they’re able to dissolve and concentrate flavor and odor chemicals. These chemicals are released into the air by the heat of cooking. That’s why you can taste sizzling bacon even before you eat it – because some of the flavor molecules are already in your nose and mouth.
Texture. Fatty foods have a special mouth feel, a special texture. Chocolate, custard, and peanut butter all melt at body temperature. When chocolate melts in your mouth, it creates a smooth, full, coating sensation that most people agree is pleasant. Fats also help distribute salts and other seasonings throughout foods – such as salad dressings – so that they make more contact with your tongue and give a deeper flavor.
A recent study from the Journal of Lipid Research states that we possess a protein that is sensitive to fat. People that show higher concentrations of this protein on their tongue are more sensitive to fat and therefore are less likely to become obese. They would feel the pleasure and fullness caused by eating less fat than people who have less of this protein. People with small amounts of this protein tend to eat more fatty foods and enjoy them less, according to these study results.
But why do we enjoy fatty foods in the first place? The answer seems to be evolution. Our ancestors used to spend their days gathering food to survive. Out of all the food they could find, fat is the best source of energy. Proteins and carbohydrates (sugars) provide about 4 calories per gram, while lipids provide 9.4 calories per gram. From the perspective of hungry cave people, fat is definitely the best choice on the menu.
Moreover, our bodies absorb fatty foods at a slower pace than proteins or carbohydrates. Fat makes us feel full, and when we feel full, our brains trigger the release of hormones that also make us feel relaxed and content.
The close tie between fat, flavor, fullness, and happiness might be an evolutionary adaptation. Generations of hungry people that had to work very hard to find their food created this response of happiness in us when we eat fat: the cave man inside us is finally satiated. So, in part, we can blame evolution for our love of junk food!
Bottom line: Fat concentrates smells and flavors in food. It gives foods a smooth creamy texture that most of us enjoy. Since fat gives us more energy than proteins or carbohydrates, it makes us feel full faster. This makes our brains release hormones that makes us feel content.