About 200 hundred television sets are in use world-wide.
1969
1969
July 20, first TV transmission from the moon and 600 million people watch.
1972
Half the TVs in homes are color sets.
1973
Giant screen projection TV is first marketed.
1954
Ray Kroc became the first franchisee appointed by Mac and Dick McDonald in San Bernardino, California
Ray Kroc became the first franchisee appointed by Mac and Dick McDonald in San Bernardino, California
1959
The 100th McDonald's opened in Chicago..
The 100th McDonald's opened in Chicago..
1955
Ray Kroc opened his first restaurant in Des Plaines, Illinois (near Chicago), and the McDonald's Corporation was created.
By 1975, sales of microwave ovens would, for the first time, exceed that of gas ranges. The following year, a reported 17% of all homes in Japan were doing their cooking by microwaves, compared with 4% of the homes in the United States the same year. Before long, though, microwave ovens were adorning the kitchens in over nine million homes, or about 14%, of all the homes in the United States. In 1976, the microwave oven became a more commonly owned kitchen appliance than the dishwasher, reaching nearly 60%, or about 52 million U.S. households. America's cooking habits were being drastically changed by the time and energy-saving convenience of the microwave oven. Once considered a luxury, the microwave oven had developed into a practical necessity for a fast-paced world.
Ray Kroc opened his first restaurant in Des Plaines, Illinois (near Chicago), and the McDonald's Corporation was created.
So you may be wondering what my point is. It isn't so much a point as a long, complicated question with multiple answers. What's the question? Why are we fat? It's a world wide epidemic. Which is quite ironic given the number of hungry people also living day to day life on this rock.
There have always been fat people in the world. There is no question about that. Some cultures considered it a sign of great wealth and fortune. In times of good fortune it was the desired norm to be chubby. But obesity at it's current levels was not an issue. The epidemic of fatness is new to the last century. The later half of it more specifically.
As I said, there have always been fat people in the world. Why is that? I've asked myself many times why I'm fat, how I got to this point. I've also asked myself why there are people in the world who can eat twice what I do, not exercise and not gain an ounce. Just doesn't seem fair to someone who gains 5 pounds at the smell of a donut.
It's such a complicated question that so many people attempt to over simplify. Some like to say it's a simple matter of calories in being more than calories out. And yes, there is some truth to this. Except, what about that friend who sits behind a desk all day eating thousands of calories, has never stepped foot in a gym and never gains anything? Oops, there goes the calorie in and out theory.
Obesity is a very complex issues. People become overweight for more reasons than I could list. The Mayo clinic has the following to say about it:
- Inactivity. If you're not very active, you don't burn as many calories. With a sedentary lifestyle, you can easily take in more calories every day than you use through exercise and normal daily activities.
- Unhealthy diet and eating habits. Having a diet that's high in calories, eating fast food, skipping breakfast, eating most of your calories at night, drinking high-calorie beverages and eating oversized portions all contribute to weight gain.
- Pregnancy. During pregnancy, a woman's weight necessarily increases. Some women find this weight difficult to lose after the baby is born. This weight gain may contribute to the development of obesity in women.
- Lack of sleep. Getting less than seven hours of sleep a night can cause changes in hormones that increase your appetite. You may also crave foods high in calories and carbohydrates, which can contribute to weight gain.
- Certain medications. Some medications can lead to weight gain if you don't compensate through diet or activity. These medications include some antidepressants, anti-seizure medications, diabetes medications, antipsychotic medications, steroids and beta blockers.
- Medical problems. Obesity can sometimes be traced to a medical cause, such as Prader-Willi syndrome, Cushing's syndrome, polycystic ovary syndrome, and other diseases and conditions. Some medical problems, such as arthritis, can lead to decreased activity, which may result in weight gain. A low metabolism is unlikely to cause obesity, as is having low thyroid function.
But weight there's more:
Obesity occurs when you eat and drink more calories than you burn through exercise and normal daily activities. Your body stores these extra calories as fat. Obesity usually results from a combination of causes and contributing factors, including:
- Genetics. Your genes may affect the amount of body fat you store and where that fat is distributed. Genetics may also play a role in how efficiently your body converts food into energy and how your body burns calories during exercise. Even when someone has a genetic predisposition, environmental factors ultimately make you gain more weight.
- Inactivity. If you're not very active, you don't burn as many calories. With a sedentary lifestyle, you can easily take in more calories every day than you burn off through exercise and normal daily activities.
- Unhealthy diet and eating habits. Having a diet that's high in calories, eating fast food, skipping breakfast, consuming high-calorie drinks and eating oversized portions all contribute to weight gain.
- Family lifestyle. Obesity tends to run in families. That's not just because of genetics. Family members tend to have similar eating, lifestyle and activity habits. If one or both of your parents are obese, your risk of being obese is increased.
- Quitting smoking. Quitting smoking is often associated with weight gain. And for some, it can lead to a weight gain of as much as several pounds a week for several months, which can result in obesity. In the long run, however, quitting smoking is still a greater benefit to your health than continuing to smoke.
- Pregnancy. During pregnancy a woman's weight necessarily increases. Some women find this weight difficult to lose after the baby is born. This weight gain may contribute to the development of obesity in women.
- Lack of sleep. Not getting enough sleep at night can cause changes in hormones that increase your appetite. You may also crave foods high in calories and carbohydrates, which can contribute to weight gain.
- Certain medications. Some medications can lead to weight gain if you don't compensate through diet or activity. These medications include some antidepressants, anti-seizure medications, diabetes medications, antipsychotic medications, steroids and beta blockers.
- Age. Obesity can occur at any age, even in young children. But as you age, hormonal changes and a less active lifestyle increase your risk of obesity. In addition, the amount of muscle in your body tends to decrease with age. This lower muscle mass leads to a decrease in metabolism. These changes also reduce calorie needs and can make it harder to keep off excess weight. If you don't control what you eat as you age, you'll likely gain weight.
- Social and economic issues. Certain social and economic issues may be linked to obesity. You may not have safe areas to exercise, you may not have been taught healthy ways of cooking, or you may not have money to buy healthier foods. In addition, the people you spend time with may influence your weight — you're more likely to become obese if you have obese friends or relatives.
- Medical problems. Obesity can rarely be traced to a medical cause, such as Prader-Willi syndrome, Cushing's syndrome, polycystic ovary syndrome, and other diseases and conditions. Some medical problems, such as arthritis, can lead to decreased activity, which may result in weight gain. A low metabolism is unlikely to cause obesity, as is having low thyroid function.
Here is a fascinating article from the CDC website:
Genomics and Health
Behavior, environment, and genetic factors all have a role in causing people to be overweight and obese
Obesity results from the energy imbalance that occurs when a person consumes more calories than their body burns. Obesity is a serious public health problem because it is associated with some of the leading causes of death in the U.S. and worldwide, including diabetes, heart disease, stroke, and some types of cancer.
Do Genes Have a Role in Obesity?
In recent decades, obesity has reached epidemic proportions in populations whose environments promote physical inactivity and increased consumption of high-calorie foods. However, not all people living in such environments will become obese, nor will all obese people have the same body fat distribution or suffer the same health problems. These differences can be seen in groups of people with the same racial or ethnic background and even within families. Genetic changes in human populations occur too slowly to be responsible for the obesity epidemic. Nevertheless, the variation in how people respond to the same environment suggests that genes do play a role in the development of obesity.
How Could Genes Influence Obesity?
Genes give the body instructions for responding to changes in its environment. Studies of resemblances and differences among family members, twins, and adoptees offer indirect scientific evidence that a sizable portion of the variation in weight among adults is due to genetic factors. Other studies have compared obese and non-obese people for variation in genes that could influence behaviors (such as a drive to overeat, or a tendency to be sedentary) or metabolism (such as a diminished capacity to use dietary fats as fuel, or an increased tendency to store body fat). These studies have identified variants in several genes that may contribute to obesity by increasing hunger and food intake.
Rarely, a clear pattern of inherited obesity within a family is caused by a specific variant of a single gene (monogenic obesity). Most obesity, however, probably results from complex interactions among multiple genes and environmental factors that remain poorly understood (multifactorial obesity).
The "Thrifty Genotype" Hypothesis
Any explanation of the obesity epidemic has to consider both genetics and the environment. One explanation that is often cited is the mismatch between today’s environment and "energy-thrifty genes" that multiplied in the distant past, when food sources were unpredictable. In other words, according to the "thrifty genotype" hypothesis, the same genes that helped our ancestors survive occasional famines are now being challenged by environments in which food is plentiful year round.
Can Public Health Genomics Help?
Currently, genetic tests are not useful for guiding personal diet or physical activity plans. Research on genetic variation that affects response to changes in diet and physical activity is still at an early stage. Doing a better job of explaining obesity in terms of genes and environment factors could help encourage people who are trying to reach and maintain a healthy weight.
What about Family History?
Health care practitioners routinely collect family health history to help identify people at high risk of obesity-related diseases such as diabetes, cardiovascular diseases, and some forms of cancer. Family health history reflects the effects of shared genetics and environment among close relatives. Families can’t change their genes but they can change the family environment to encourage healthy eating habits and physical activity. Those changes can improve the health of family members—and improve the family health history of the next generation.
How Can You Tell If You or Your Family Members Are Overweight?
Most health care practitioners use the Body Mass Index (BMI) to determine whether a person is overweight. Check your Body Mass Index with a BMI calculator.
Key References
- Bouchard C. The biological predisposition to obesity: beyond the thrifty genotype scenario
. Int J Obes 2007; 31:1337-9. - Bouchard C. Defining the genetic architecture of the predisposition to obesity: a challenging but not insurmountable task. Am J Clin Nutr 2010; 91:5-6.
- Choquet H, Meyre D. Genetics of obesity: what have we learned? Curr Genomics. 2011;12:169-79.
So, can you or I blame genetics for our obesity? Yes and no. There is some scientific evidence that certain people are more prone to run a little fluffy than others. But there is far more to it than that. It is not nearly as simple.
Did you understand that? Let me summarize. We live in a society that makes it easy to be fat. We have a drive through on every corner and a convenience store on the other. We have microwaves and frozen dinners. We have computers, televisions with remote and 2000 channels. Our jobs have become less and less active. Our food has become more and more processed. We move less and we eat more.
Lets talk about why I'm morbidly obese. I just recently figured all this out so it's a bit new to me. I am one of those people with the genetic predisposition. I get fat easy and I stay that way. My body loves to be covered in pound upon pound of excess fuel. After all, I may need it over the winter. Except that winter never comes so I don't burn it off, only store another winters worth on top. And so it goes.
The brain regulates food intake by responding to signals received from fat (adipose) tissue, the pancreas, and the digestive tract. These signals are transmitted by hormones—such as leptin, insulin, and ghrelin—and other small molecules. The brain coordinates these signals with other inputs and responds with instructions to the body: either to eat more and reduce energy use, or to do the opposite. Genes are the basis for the signals and responses that guide food intake, and small changes in these genes can affect their levels of activity. Some genes with variants that have been associated with obesity are listed in the Table.
Energy is crucial to survival. Human energy regulation is primed to protect against weight loss, rather than to control weight gain. The "thrifty genotype" hypothesis was proposed to help explain this observation. It suggests that the same genes that helped our ancestors survive occasional famines are now being challenged by environments in which food is plentiful year round.
I am also a product of my environment, like many of us. I never learned what food was really for. I never learned to look at food as a fuel. I looked at food as a comfort. As something to be horded. As my only friend. And to be completely honest, I developed an unhealthy love for food. It replaced the intimacy I was never able to develop with anyone or anything else.
So the question becomes, how much of it is genetics, how much of it environmental and most importantly, how much of it is personal choice? Diet, while somewhat dependent on socioeconomic circumstances and environment, is also largely left to personal choice. Yes, it's cheap and easy to go to the store and buy junk. Cooking can be difficult, expensive or completely foreign. What if you never learned to cook? A product of your environment. What if you never learned what was and was not healthy?
Some people grow up in highly active households. They learn this behavior and consider it normal. Other people grow up in households that revolve around the television and an active lifestyle is completely foreign to them. How much of obesity is nature and how much is nurture? I'm still not entirely sure.
I do know a few things. It can't all be blamed on genetics, nor can it all be blamed on everything else. But it's not an absolute. If a mentally handicapped person can learn, if a physically handicapped person can win a race, row a boat, ride a bike and all the other things they do, then I can overcome my genetic predisposition and life a healthy lifestyle. I can relearn what many people already know how to do. I can make better choices in what I eat, I can increase my activity level. It may not be easy, but it's far from impossible.
Introduction: Rising rates of obesity seem to be a consequence of modern life, with access to large amounts of palatable, high calorie food and limited need for physical activity. However, this environment of plenty affects different people in different ways. Some are able to maintain a reasonable balance between energy input and energy expenditure. Others have a chronic imbalance that favors energy input, which expresses itself as overweight and obesity. What accounts for these differences between individuals?
| What We Know: | What We Don’t Know: |
|---|---|
| Biological relatives tend to resemble each other in many ways, including body weight. Individuals with a family history of obesity may be predisposed to gain weight and interventions that prevent obesity are especially important. | Why are biological relatives more similar in body weight? What genes are associated with this observation? Are the same genetic associations seen in every family? How do these genes affect energy metabolism and regulation? |
| In an environment made constant for food intake and physical activity, individuals respond differently. Some people store more energy as fat in an environment of excess; others lose less fat in an environment of scarcity. The different responses are largely due to genetic variation between individuals. | Why are interventions based on diet and exercise more effective for some people than others? What are the biological differences between these high and low responders? How do we use these insights to tailor interventions to specific needs? |
| Fat stores are regulated over long periods of time by complex systems that involve input and feedback from fatty tissues, the brain and endocrine glands like the pancreas and the thyroid. Overweight and obesity can result from only a very small positive energy input imbalance over a long period of time. | What elements of energy regulation feedback systems are different in individuals? How do these differences affect energy metabolism and regulation? |
Rarely, people have mutations in single genes that result in severe obesity that starts in infancy. Studying these individuals is providing insight into the complex biological pathways that regulate the balance between energy input and energy expenditure.
| Do additional obesity syndromes exist that are caused by mutations in single genes? If so, what are they? What are the natural history, management strategy and outcome for affected individuals? |
| Obese individuals have genetic similarities that may shed light on the biological differences that predispose to gain weight. This knowledge may be useful in preventing or treating obesity in predisposed people. | How do genetic variations that are shared by obese people affect gene expression and function? How do genetic variation and environmental factors interact to produce obesity? What are the biological features associated with the tendency to gain weight? What environmental factors are helpful in countering these tendencies? |
| Pharmaceutical companies are using genetic approaches (pharmacogenomics) to develop new drug strategies to treat obesity. | Will pharmacologic approaches benefit most people affected with obesity? Will these drugs be accessible to most people? |
| The tendency to store energy in the form of fat is believed to result from thousands of years of evolution in an environment characterized by tenuous food supplies. In other words, those who could store energy in times of plenty, were more likely to survive periods of famine and to pass this tendency to their offspring. | How can thousands of years of evolutionary pressure be countered? Can specific factors in the modern environment (other than the obvious) be identified and controlled to more effectively counter these tendencies? |
What It Means
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