About ten years ago I was visiting an older friend in a Southwest desert town. While we were eating at his favorite local Mexican restaurant, he mentioned that he was never hungry. At the time I thought that was an odd statement because he was eating his professed favorite dish right there in front of me. He was thin but had been a farmer all his life and at 75 years old was obviously keeping himself sufficiently nourished to remain upright and physically active. When asked to clarify, all he could do was reiterate that he never really felt hungry. At the time I could not fathom how that could be so.
Recently, I’ve been thinking about what hunger actually is. The idea is expressed in a number of contexts so let me give some examples:
- “I feel hungry for a pizza.”
- “My blood sugar is low. I need to eat.”
- “After working all day, I am starved.”
- “It’s 6 pm. What shall we have for dinner?”
The explanations for the above statements might be:
- The word ‘hungry’ is a synonym for a particular food desire. Pizza is a food choice not necessarily what the body needs for nourishment.
- Someone may feel weak, lethargic or emotionally uneasy for a complex number of reasons. This may or may not be due to low blood sugar but often eating helps to alleviate the symptoms of discomfort.
- If one does significant exercise or simply endures for a number of hours without eating, one may find they have a strong appetite.
- A clock does not control your desire for food. Your mind is trying to force compliance to a contrived idea. The body’s need for food is real. What is considered food and when to eat it is another question.
Food has calories. Or, does it?
A calorie is a measurement of heat. This was useful during the era of steam engines as applied to the heat released from coal and oil. This does not apply to the world of biology or modern physics. Food is not burned in the living body. The biologic idea of a calorie does not have any relevant truth in it even though it is repeatedly printed on food labels and diet/nutrition books as though it does. Calories in (food), calories out (energy expended) is a false statement. Do you think that the calorie equivalent 4 ounce piece of cooked Chinook salmon verses a 2.13 oz. 3-Musketeers candy bar is going to have the same energizing effect for the body in the short term or in the long term? You might consider this example unfair because the candy bar is 67% pure sugar and the salmon has no sugar. Half the salmon’s calories are from fat. A portion of that fat is an omega-3 fat known as DHA and is not broken down for energy because it is so precious to the human body it is conserved and appropriated into brain and nerve tissue.
Confused? It seems like the food peddlers are fine with twisting facts. Selling low nutrient synthetic food as though it was real food is a profitable game.
Unfortunately, food is complicated. Why our bodies need food is even more complicated. How a diet of specific foods ultimately affect our body is not well understood. But let’s not get overwhelmed by a tsunami of ignorance and start from the beginning.
I wrote last time (Dehydration article) that the cells of the body extract electrons from the food we eat. Notice that calories are not part of that picture. Food does not burn like wood in a fire. Electrons through a complex process in each cell’s mitochondria (tiny cells or organelles within each cell) are used to produce ATP. ATP pumps the proteins, DNA, etc. in the cell with energy to allow them to open their physical structure like an umbella so that water can form a multi-layered coating. These physically structured layers of water form a liquid crystalline semiconductor (not unlike silicon electronic semiconductors) that is part of a body-wide network that connects all tissue and cells. The energizing of this system from various sources is the big picture of energy in the body.
The electrons in food are like the electrons in a battery charger. The molecules of ATP are like charged batteries. They move from the mitochondria out into the rest of the cell to discharge their energy where it is needed. In the process of discharging, ATP lets go of a phosphate group and becomes ADP (adenosine di-phosphate instead of tri-phosphate). The exact details do not matter but the concept I would like to impress is that ATP is recycled up to 10,000 times per day by the heart and many hundreds of times in the average cell. How much ATP you have in your body and how fast you can recycle it is going to affect how much energy you feel you have. If you have less ATP you need to eat more often to provide more electrons. There is a temporary storage of electrons in the form of glycogen (sometimes called animal starch) in the liver as well as in the form of fat in adipose tissue found throughout the body. People’s ability to use glycogen and fat is a critical source of energy but varies greatly.
How much energy you have in the moment does necessarily depend on what you ate last and/or exactly how many micro-nutrients (vitamins, minerals, etc.) were consumed. Of course, long term this does matter. Just look at the effects of typical poor-quality restaurant food and processed supermarket food is having on modern populations. What does matter short term (i.e. during the day) is the body’s ability to maintain the efficient flow of electrons to regenerate ATP.
How does it make sense if you feel hungry two hours after eating a meal or even after 4 or 5 hours? Real hunger is due to a perceived lack of functional energy. All of us have plenty of body fat to survive nicely without food for much more than a few hours. Even if you have no glycogen stored in the liver (not likely), the body can obtain a day’s worth of energy from less than a pound of fat. This means that, short of starvation, true physiological hunger could be considered a dysfunction of the body. On a daily basis most of us more than adequately keep up with our energy needs from food.
The two main sources of electrons from food are carbohydrates and fats. The other macro-nutrient protein is metabolically and economically problematic at being the major source of food electrons. Protein does supply amino acids that are necessary for building or rebuilding our tissues and enzymes. Excess or damaged amino acids eventually have their nitrogen stripped away by the liver and they are broken down for their electrons similarly as carbohydrates.
There has been a big debate as to whether carbohydrates (i.e. sugars and starches) or fats or some magic combination of them should supply us with the food energy we need. For the moment, forget about whether there is a need for specific essential carbohydrates (there is none) or essential fats (there are several). Forget about the necessity of oil-soluble vitamins such as A, D, E & K and other micro-nutrients only found in fats. Let’s just consider how the body assimilates and utilizes carbs and fats.
Fat vs. Carbs
The manner in which these two nutrients get manipulated at the cellular level is quite different. Both ways eventually create ATP for the cell’s use. Fat produces more calories per gram – 9 verses 4 for carbs. That is a little bit over twice as much per given weight. But we are not burning food. We are turning it into energized ATP. Carbs, specifically glucose, produce about 36 ATP/mole. Fat, specifically the common fatty acid palmitic acid, produces about 147 ATP/mole. (In chemistry, a mole is a specific number of actual molecules). That is a four-fold difference per molecule and a three-fold difference figured on a gram for gram basis.
If you were inclined to think that you could just eat more carbs to get the same energy as fat there is a functional as well as a qualitative difference to consider. You have probably watched documentaries about explorers or scientists who try to survive at the frigid poles of the earth. Their food cravings are not normal. It is universally spoken that there is a desire for fats – sometimes in the size and shape of a stick of butter! Why? The need for calories (actually electrons) is so great that significant amounts of dietary fat are the body’s preferred energy source. The cold temperature also shifts the cellular biochemistry and metabolism towards the processing of fat. Eating more carbs is not what the body wants in those circumstances. Extracting electrons from carbs is not efficient compared to fats. The biochemistry and biophysics of this situation is not simple to explain but when it’s cold, fat is what the body craves.
So if we are not in Antarctica, why would fats be good for us? In a word: efficiency. A lack of efficiency means waste and tissue wear-and-tear. Most adults have various levels of mitochondrial dysfunction. Most children, on the other hand, are energy machines. Carbs that are being processed in the adult mitochondria tend to create high amounts of reactive oxygen species (ROS) which causes oxidative damage to the very complex molecular machinery. The body can produce anti-oxidant compounds such as glutathione and super oxide dismutase but again that ability is limited in a typical older person. Anti-oxidants found in food have limited value in this situation. Without sufficient protection, mitochondrial function gets further chipped away over time.
The less efficient the mitochondria are the less energy you have. There is no way around it. The less energy you have the less able you are to maintain your body over time. Sure you can conserve your energy by behavior modification but that is just buying some time. Except by a fatal accident, death is a usually a slow process of metabolic failure until a final catastrophic failure (e.g. heart attack, stroke, organ failure, cancer, etc.) totally disables one or more critical body functions.
The curious part is that eating a rational fat-dominant diet actually normalizes the body’s fat stores. As the author Covert Bailey characterized – “become a better butter-burner” – means that you increase the body’s ability to use fat for energy both from the diet and from your own adipose tissue. This is a huge advantage. Instead of frequently stoking your ‘fire’ with kindling (i.e. carbs), you can enjoy the more constant ‘heat’ from a long-burning log (i.e. fat).
One of the biggest bugaboos that people have regarding the consuming of fat is the 50+ year old fear of cholesterol. That mind-virus will be a topic in the future.