Fear of Food
Confront your fear and prolong your life with the dietary strategy known as “calorie restriction”
Many Americans fear food. I’m not referring just to those with eating disorders, for whom food is deadly, or fashion models who must watch their figures to stay employed. I’m referring to health-conscious Americans who don’t know what diet is healthiest. This fear is stoked by headlines such as “Excess salt blamed for 2.3 million excess deaths” and “Sugary drinks may explain 180,000 deaths worldwide.”
We live in an age in which nutritional superabundance threatens our health. The Industrial Revolution in the 18th and 19th centuries increased the standard of living in industrialized countries, allowing a transition from a plant-based diet, which includes only a limited amount of meat, to one based on meat. This change occurred simply because humans prefer the taste of the more expensive meat-based diet.
This transition increased the incidence of many diseases: heart attacks, strokes, high blood pressure, type 2 diabetes, obesity, hypercholesterolemia, and metabolic syndrome. I call these the “diseases of superabundance.” The higher standard of living achieved in China, India, and other countries in recent decades has caused heart attacks to become the leading cause of death worldwide.
One hundred years ago, people who lived into their sixties and beyond did not die of these diseases. They are not the inevitable consequence of aging. This fact has been forgotten because generations of physicians have practiced during the era of superabundance.
There is no doubt that the wrong diet can shorten lifespan. This is shown by the increased number of deaths due to heart disease following the introduction of industrially-produced trans fats in the U.S. in 1911. These are made by chemically solidifying the unsaturated fats in liquid vegetable oil to make an inexpensive alternative to animal lard.
Beginning in 1913, deaths due to heart disease in the U.S. increased until the late 1960s, interrupted only by rationing and shortages due to world war (Figure 1). Those data show in granular detail how closely the incidence of death due to heart disease follows the food supply.
In the 1980s experts recommended trans fats as a healthier alternative to saturated fats, which had been linked to an increase in cardiovascular deaths. However, trans fats are even worse. Retrospectively, they are now estimated to have caused as many as 250,000 excess fatal heart attacks annually in the U.S. before legislation finally limited their consumption. As a cause of death done to himself, trans fats only trail war, air pollution, and cigarette smoking.
The harm caused by trans fats was so subtle that legislation limiting their consumption was not introduced until 2003, in Denmark. Over the next 3 years, deaths due to cardiovascular disease decreased an average of 14.2 per 100,000 people. Labeling which boasts “0% Trans Fats” must be greeted with mixed emotions by health-conscious consumers of a certain age, whose arteries may have already been damaged by them.
When the cause of a disease is known, it can be controlled. Infectious diseases like polio, nutritional diseases like scurvy, and genetic diseases like phenylketonuria, more commonly known as PKU, are examples. Every newborn in the U.S. is screened for PKU, which is controlled with diet. Consequently, neurologic damage caused by PKU is very rare.
Many physicians believe that lowering cholesterol levels is the best way to prevent heart attacks, and dietary salt causes high blood pressure. However, lowering cholesterol levels did not decrease cardiovascular deaths in 44 prospective, randomized, controlled studies. Data published in 2019 show that U.S. deaths due to heart disease increased 4% in those aged 45 to 64 between 2011 and 2017.
The age-adjusted mortality rate from cardiovascular disease due to high blood pressure increased by 0.5% per year from 2000 to 2018. Quite simply, cardiovascular diseases have not been controlled. For savvy medical consumers, data like these create a medical credibility gap, which worsens the fear of food.
One solution to the fear of food might be to eat what ancient humans did on the assumption that this is what man evolved to eat. The latest research suggests that the diet of early humans was determined by climate: the earliest humans in Northern climes ate a meat-based diet and those in warmer climes ate a plant-based one. Early humans probably ate whatever was available. They just didn’t have the luxury of being choosy.
Of the excess number of fatal heart attacks caused by trans fats, only 30% can be blamed on blood cholesterol levels. Most of the harm caused by trans fats and saturated fats from a meat-based diet is due to their impact on blood viscosity. Viscosity describes a fluid’s thickness and how easily it flows (Figure 2).
Honey is more viscous than water and flows more slowly. The role of increased blood viscosity in disease has been overlooked and prevented the diseases of superabundance from being controlled.
Trans and saturated fats increase blood viscosity, largely through their impact on the flexibility of red blood cells. Red blood cells are the most pliable and numerous cells in the body (Figure 3). Flexibility is necessary so they can squeeze through the smallest blood vessels, which have diameters smaller than red blood cells.
When the membranes of red blood cells are made of saturated and trans fats instead of unsaturated fats, they lose flexibility for the same reason that trans and saturated fats are solid and vegetable oils are liquid.
Stiffer, less flexible red blood cells increase blood viscosity. Thicker blood requires more pressure to make it flow. Thus, elevated blood viscosity contributes to high blood pressure. As anyone who has seen blood clot in a tube knows, it must flow to stay liquid. As blood becomes more viscous, its flow becomes progressively sluggish until it clots, causing heart attacks, strokes, and pulmonary embolism (blood clots that block flow to the lungs).
After a meal, muscles take up and store glucose from the blood. Thick blood cannot flow as easily through the smallest vessels, preventing muscles from taking up glucose as well as they should. Glucose stays in the blood longer, raising blood levels. This problem is worsened by sugary food. Thus, increased blood viscosity causes type 2 diabetes.
All the diseases of superabundance either cause or are caused by increased blood viscosity. It is the fundamental abnormality of the diseases of superabundance.
According to the superabundance theory of nutritional diseases, the most direct approach to their management is to eat less. This approach, called “calorie restriction,” is supported by more data than any other dietary strategy. A balanced diet and adequate intake of essential minerals and vitamins must be maintained.
A 25% reduction in calorie intake was tested in a prospective randomized, controlled study called the Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy (CALERIE) study, sponsored by the National Institute on Aging of the National Institutes of Health (NIH). After two years, calorie restriction decreased LDL (the bad cholesterol), blood pressure, glucose, triglycerides, and insulin levels, and increased HDL (the good cholesterol). Lower LDL and triglyceride levels and higher HDL levels will reduce blood viscosity. Calorie restriction did not decrease the quality of life.
Red blood cells became more rigid as calorie intake increases, and blood viscosity increases with increased carbohydrate intake. Thus, the most successful strategy to prolong lifespan is calorie restriction, not high carb and low fat or vice versa.
CALERIE confirms the lesson from wartime rationing and food shortages: superabundance causes heart disease. Calorie restriction also increases the lifespan of organisms that do not have a cardiovascular system, such as yeast and small worms called nematodes. This is because calorie restriction decreases the metabolic rate by decreasing thyroid hormone levels without causing hypothyroidism. This may decrease the production of free radicals which cause mutations. These are theorized to contribute to aging. Fewer mutations could also explain why calorie restriction decreases the incidence of cancer.
Superabundance theory suggests another approach to managing these diseases: blood donation. New red blood cells are more flexible than the ones they replace, reducing blood viscosity. A prospective randomized trial showed that donating approximately two units of blood over six weeks reduced fasting blood glucose from 111 mg/dL to 99 mg/dL (normal <100 mg/dL) and blood pressure from 149/93 mmHg to 131/84 mmHg.
This study shows the dependence of blood glucose levels on blood flow and the dependence of blood pressure on blood viscosity. In a study from Finland, blood donors had an 88% decreased risk of heart attacks over 9 years. That study shows the importance of blood viscosity in heart disease. These studies must be confirmed so that blood donation is added to our therapeutic armamentarium. However, these results are consistent with the best available data and there is no reason to not donate blood now.
Superabundance thickens both our waistlines and our blood. Intuitively, calorie restriction makes sense as a remedy for the diseases of superabundance. This strategy is reminiscent of the timeless advice of Paracelsus, the Father of Toxicology, who wrote in the sixteenth century: “Poison is in everything, and nothing is without poison. The dosage makes it either a poison or a remedy.”