Fat Genes, Skinny Jeans: Epigenetics

Is it nature or is it nurture? What counts more, your genes or your environment? What percentage of our behavior is predetermined, and what percentage can we change? These questions are best left to the pot-smoking teenagers on “That 70’s Show” and not to scientists and educators. No answer is possible and the argument is pointless. It is never OR and always AND. It is always a two-way street, an interaction. There is only nature AND nurture, genes AND environment.

From the moment of conception the human organism is always adjusting to the external environment. Initially, that external environment is the prenatal environment of the maternal womb. But that small world is still constantly fluctuating. Every fetus is bathed in amniotic fluid and nourished via the umbilical cord from a mother who is also reacting and changing in response to her own environment. For example, we now know that babies are much more accepting of new foods when their mother has consumed these foods during pregnancy. In other words, an easy way to help your child “like carrots” is to eat carrots during pregnancy. The unborn baby will then experience an environment that includes exposure to carrots. This environment, like all environments, changes the baby’s brain. Carrot-exposed fetuses are much more likely to be carrot-accepting babies or children. This makes sense. For most of human history people would have had a fairly limited diet that reflected their culture, climate and geography. The prenatal environment is where we begin learning how to eat. The system is well designed to prepare us for the diet that the baby is likely to eat.

Of course, in the modern world we eat food from many cultures and many climates year round. We also eat a lot of synthetic food or chemicals that look and taste like food, but are really food facsimiles. This requires a lot of learning and adaptation from our brains and nervous systems to maintain homeostasis. Homeostasis is our biological recalibration of our internal environment in response to world around us.

Our nervous system survey, filter and attend to what is important based on previous learning and experience. This is done automatically. The brain, which is the processing part of the nervous system, also uses learning and experiences to make decisions about possible ways to restore homeostasis. The possibilities are infinite, but some choices are more effective and/or more efficient than others. The nervous system is also responsible for signaling effectors—muscles, glands and even cells—to move in certain combinations and intensities. Finally, the effectors relay feedback to the brain that is stored for future reference. Was this a good decision? Should we do this again in the future? Was the response too much? Too little? Too late? Too early?

We don’t just store information in a filing cabinet—we update our software. We do this through epigenetics, which literally means “above the genes.” DNA is not destiny, but neither are we just “a blank slate” completely shaped by our experiences. DNA is just a recipe for proteins. Our “genes,” which are contained on 23 paired chromosomes, are recipes for every kind of protein our bodies would ever need. You could think of our DNA as a large cookbook containing all the recipes that have ever existed.

But our genes aren’t just these recipes—they are like the personal cookbook of a brilliant and creative person (you) containing millions of notations and changes. This epigenetic information changes how and when recipes will be made.

Fans of the Harry Potter books and movies recall the advanced potions book that Harry had the good fortune to acquire in Harry Potter and the Half-Blood Prince. Filled with accessory instructions and substitutions, these recipes transformed Harry from a very mediocre potions student to a regular whiz kid, much to the dismay and despair of perpetual top student Hermione Granger. By using Severus Snape’s old potions cookbook, Harry was able to take advantage of all the experiences and learning that Snape had been forced to get the usual way.

Humans have only about 20,000 protein coding genes, which is about 1% of what was predicted when the project began in 1990. Even more astonishing, the DNA (the protein coding portion) accounts for less than 2% of the total genetic information. We are only now beginning to comprehend that what scientists used to call junk or nonsense is actually where all the regulatory information is stored. And this information is modified by environmental experiences like stress, nutrition, toxins and even our relationships with other people. Not only that, but these changes can be passed on to our offspring, just like Snape’s Potions book was passed on to Harry Potter!

DNA is not destiny. Genes are really our talent — what we inherit at birth. But we have infinite capacity to refine and change our recipe book. Humans are naturally fat. It’s programmed into our DNA to allow for us to grow and fuel our large brains. But we are not naturally obese. The way we eat is changing us, and not in a good way. We need to understand and accept that scientists can be way off in their “predictions.”

Nutrients are chemical compounds observed in nature, then reproduced in a laboratory and then a factory. These nutrient chemical compounds might not be nourishing us as well as commonly assumed in conventional dietary and health advice. Humans also snack often and eat a lot of carbohydrates. This keep insulin levels persistently elevated. Humans can’t release weight because our bodies are first stalled and then stuck in accumulation mode.

Modern humans have radically changed our dietary habits—the when, what, where, who, how and why of eating behavior. Our fat genes are getting fatter, because we are making too many changes without careful observation and follow-up. We need a little more Half-Blood Prince and a little less “wiki.”

A wiki, as in Wikipedia or WikiTravel, is a website that enables quick content addition and editing by groups of people. Those groups can be very large. Wiki is now the way of the world, especially the World Wide Web. The information bloat we see online is very similar to the bloat we are beginning to see on our bodies.

We can only learn to control the inflow of information about food, exercise, disease, nutrition, and supplements by learning to filter, not funnel. A funnel is putting your hands over your ears and closing your eyes while you chant “too much, too much, too much.” It’s a survival mechanism for dealing with overload.

Survival mode is stressful. It often drives people to escapist behaviors. In the mid-18th Century, London saw unprecedented growth, urbanization and social change. Food prices dropped and people had more disposal income. They chose to drown their troubles. Gin shops were abundant. In London alone (which then had as many residents as does Columbus, Ohio today) there were over 6,000 gin shops, and that’s not counting the street vendors. Initially people were drunk and disorderly—then they became too drunk to be disorderly. Bad weather, a depressed economy and a later drop in disposable income closed the door on this untidy chapter in history.

When people have dramatic changes in their environment they first go into survival mode, but they cannot stay there. Survival mode is stressful and exhausting; eventually we must adapt. The modern environment is a deluge, and we must begin to make choices. We can’t keep gobbling to keep up, not with the information, and not with the food. When we can’t get out of the rain, an umbrella can be very useful. It keeps out some of the deluge while we figure out what to do next.

What to do when the world views conflict with the world cues?

We are suffering from excessive input. We think the problem is that we are putting too much in our mouths. The reality is we are putting too much in our brains. The nervous system is a chain that begins with information gathering. When there is inadequate filtering, then the processors get overloaded and can’t make good decisions. When we focus efforts on outcomes, we can alter results, but we can’t solve the real problem.

Just like London during the gin craze, we can’t halt progress. We must develop the right skill set for our environment. We live in a world that tells us “happiness will come when you can fit in those skinny jeans.” But our nervous system cues us to engage in behavior that can only result in fat accumulation and undesirable, excess weight. No skinny jeans for us, not even spandex. Without some filtering skills, this environment dictates that fat genes will need a spandex upgrade. Perhaps “exSpandex” to accommodate our broken and out-of-control weight regulating mechanism.

The happy news is that genetics doesn’t have the final say. Our behavior and environment can change our genes. That’s the beauty of epigenetics. To change our habits we must learn and master a new skill set.

“Every man can, if he so desires, become the sculptor of his own brain.”
— Santiago Ramón y Cajal

“If people knew how hard I worked to get my mastery,
it wouldn’t seem so wonderful at all.”
— Michelangelo

Finally, here is a quote from Arthur Conan Doyle (from “A Study in Scarlet”):

“I consider that a man’s brain originally is like a little empty attic, and you have to stock it with such furniture as you choose. A fool takes in all the lumber of every sort that he comes across, so that the knowledge which might be useful to him gets crowded out, or at best is jumbled up with a lot of other things, so that he has a difficulty in laying his hands upon it. Now the skillful workman is very careful indeed as to what he takes into his brain-attic. He will have nothing but the tools which may help him in doing his work, but of these he has a large assortment, and all in the most perfect order. It is a mistake to think that that little room has elastic walls and can distend to any extent.

Depend upon it, there comes a time when for every addition of knowledge you forget something that you knew before. It is of the highest importance, therefore, not to have useless facts elbowing out the useful ones.”

DrTheresa.com, Theresa Nesbitt and her publications provide general information on health and wellness. This general information is not a substitute for health advice and medical care from physicians who know you. Please talk to them before making significant changes in your lifestyle. Complete Terms of Use and Disclaimers