Why do we eat? Well, the obvious response to this question is that we eat to get energy or we eat to survive. At the base, this is the reason why we eat. All life forms need food to survive. No creature is self-perpetuating on its own. But how do we decide what, when and how much to eat? A number of factors are responsible for this. Let’s consider them.
Physiology
Hunger is controlled by the hypothalamus in the brain. The hypothalamus tells us if we need to eat more or stop eating. It may receive signals based on the amount of food in our stomach. For example if we have a full and distended stomach the high pressure will be detected and messaged to the hypothalamus via nerves to tell it to shut off hunger receptors. The hypothalamus may also be influenced by a number of hormones. For example:
- Insulin – Produced in the pancreas and released in response to increased glucose in the blood and signals the hypothalamus that you are full
- Glucagon – Produced in the pancreas released in response to low glucose in the blood and signals the hypothalamus that you are hungry
- Ghrelin – Produced in the stomach and released in response to empty stomach and and signals the hypothalamus that you are hungry
- Cholecystokinin (CCK) – Produced in the small intestine and released in response to full stomach. It signals the hypothalamus that you are full
- Leptin – Produced by adipose (fat) cells in the body and signals the hypothalamus to close more hunger receptors over the long term
Taste
Food is meant to be enjoyed. That’s why they have different tastes and flavors. Think of a mango, or whatever your favorite fruit is and consider how delicious it is. We generally make decisions on what and how much to eat based on taste. Yes, I know that we would like to think that we are making our decisions based on what is healthy and good for our body but the truth is that most of us go for taste first and then health. Food scientists have the challenge of developing foods that are both tasty and healthy. This can be hard to do for food scientists, and it may be equally hard for the greatest cooks in the world – moms. Beware, when mom says “I prepared something healthy for you”, it might be a code for, “it ain’t taste that good.
Culture
Depending on the culture you are from, food traditions and food preparation styles may have been passed down to you from many generations. These traditions may be based on availability of food in a specific region, festivals, religious practices, or simply methods of cooking that have been perfected for hundreds of years. When you think of Mexican food, tacos or burrito may come to mind. When you think of Indian food, you may think of dal and curry. It’s hard to imagine anyone else doing a better job at these cultural cuisines.
Emotions
How we feel can affect what and how much we eat. Some People may binge on ice cream because they or sad or they may binge on it because they have something to celebrate. If I am anxious, nervous, very annoyed, or otherwise stressed, it kills my appetite. However, there are people who will eat more when they are stressed. Emotion is a complex thing. People respond in their own unique way to what they are feeling.
Habits
Do you eat popcorn at the movies? If you do, it’s probably not because you are hungry or could not choose something else, but that it is ingrained as a habit. For example, for years theaters have thrived financially not so much on the movies they show but on popcorn. Popcorn is really the main event. The movie is just the “sideshow”. Eating a light breakfast and a big dinner is another habit that many of us learned pretty early in life. Who says breakfast, the first meal of the day can’t be the size of dinner?
Social Events
Consider the last time you felt stuffed at Thanksgiving or party? The combination of good friends, good emotions, and good food makes us want to eat or drink more. Alcohol drinking for example tend to peak when we are having a good time at social gatherings around people who we are comfortable with.
Availability
Some foods are simply not available where you live due to seasonal or other environmental constraints. Luckily, with food preservation and processing we can purchase foods that were produced thousands of miles away. A favorite food of mine is Jamaican cooked Ackee and saltfish, which happens to be Jamaica’s national dish. With international transportation and shipping I can get this delicacy within 2 hours from where I live (not a big sacrifice for awesome food!).
Costs
The amount of spending money we have is going to be always limited. Hence, we make decisions based on affordability. All being equal, it just make sense to buy the less expensive item. I remember visiting a sugar factory some years ago as part of a college field trip. I noticed something rather interesting in the factory. The finished product emerging from a storage bin, separated into two different packaging lines. One line was a cheap store brand and the other was a high-end brand. They were both identical products. However, eventually consumers would be paying more for the high-end brand believing it was better.
Marketing and Brand Perception
The previous story points to the fact that consumers care about brand. They associate brand with quality. As long as they are convinced that they are getting a better quality, they will pay more. So, if you are a Baker, you don’t have to make the world’s, best bread but you certainly must convince your customer that that is what they are getting.
Convenience
Who doesn’t want to save time? Some foods offer more convenience than others based on how they might be packaged or processed. A made-from-scratch home-made meal may sound good, but your busy lifestyle might not allow you to do this and get other stuff done that you need to accomplish. In that case a frozen dinner meal may provide just the magic you need.
Environment
We also make decisions about what we eat based on the environment in which we live, work and interact. For example, if you work in a restaurant or factory that gives you access to foods that you love, you may end up selecting to eat more of that food. It would also be true that just passing a bakery and smelling freshly baked bread can pull you in the store and get you to buy bread and perhaps the other treats as well.
Why do we eat? Well, the obvious response to this question is that we eat to get energy or we eat to survive. At the base, this is the reason why we eat. All life forms need food to survive. No creature is self-perpetuating on its own. But how do we decide what, when and how much to eat? A number of factors are responsible for this. Let’s consider them.
Reference: Thompson,& J., Manore, M., Vaughan, L. (2020). The science of nutrition (5th ed.). New York. Pearson
