We need to eat food to live. However, what and how we eat are things that we do without much thought and with even less knowledge. That is a dangerous situation in a world where most are getting fat.

The types of food and amounts we eat are determined by a number of different factors, including:

• Availability of food
• Personal likes and dislikes
• Cultural and religious factors
• Family preferences
• Medical and health limitations

I am not talking about being able to find food but rather what types of food are available to us. Obviously, some foods are seasonal and not available year-round (though the number is shrinking in the US supermarket). Geography plays an important role in this also; the Japanese eat a lot of fish because they live on islands.  Other foods have availability based on supply and demand, etc. In the urban areas of the United States it is common to drive for blocks without seeing a supermarket or grocery store. Instead, the food available is only from fast food restaurants that provide a high-calorie high-fat meal at a ridiculously low cost. If good food is not available, you will not have a chance to buy or eat it. Studies have also shown that the more choices we have in a store or in our fridges, the more food we will eat.

It turns out that there are real scientific reasons that exist when we say that we do not like a particular food. Research has shown that we have special genetically determined taste buds  that are unique to each of us. Even though some of us may taste a food and say it tastes sweet, in fact it tastes slightly different to each of us. If you lack the genes needed to detect some tastes, the food may taste bitter or sour to you, and you’ll say, “I don’t like that.” A famous example is former president G.H. Bush, who hated broccoli; it tasted bitter to him. Other factors include allergies to foods or an inability to digest some foods. For example, I am lactose intolerant and cannot digest pasteurized milk. Raw milk has bacteria that produces an enzyme called lactase that digests the lactose sugar in milk. All of us have that enzyme in us as children. Pasteurized milk destroys the bacteria and the enzyme, so people like me who have lost the enzyme with adulthood cannot digest the milk!

When my family was still young, we would typically have three courses for dinner: soup, a main dish and dessert. As everyone grew, including my wife and I, we have decreased our food intake by cutting back to two courses—fewer calories.

We also have family preferences; for example, none of us likes sweetbreads and most of us hate liver. Every week, though, we have a nice Persian rice dish and a good Italian pasta.

There are a number of foods that we cannot eat due to individual health considerations. It has been a while since I ate an egg without some thought of its cholesterol content. Likewise, diabetic patients must be careful to limit their sugar and carbohydrate intake.