Dr. Pressman

Personal Nutrition
An Overview of Nutrigenomics
Author: Alan H. Pressman, D.C., D.A.C.B.N. & Isis Medina, D.C., D.A.C.B.N.

Introduction — The Road to Personalized Nutrition

Wouldn’t it be wonderful if you knew exactly what you yourself could do to live a healthier life? How you could make the aging process as graceful and as long as it should be? Which vitamins and minerals and other supplements work best for you — and which don’t?

Well, the wonderful world of genetics is making that possible — today.

Genetics is the most exciting thing that’s ever happened in the world of clinical nutrition and health. Ever! Even if you go all the way back to Hippocrates, nothing is more exciting than what’s going on right now — a total change in the model of health and well-being.

It started in 1990 with the Human Genome Project, an effort to create a roadmap of all our genes. In 2001 the project published a working draft of the map and promised to complete it by 2003. And it did, right on time. As the genome was being mapped, the so-called SNP Consortium started researching differences in our genes that help explain why people respond differently to pharmacological treatment and nutrition. Understanding these differences paves the way to targeted pharmacology and customized nutrition.

It’s happening today. We call the new science of personalized nutrition nutrigenomics or sometimes nutrigenetics or nutragenetics. It’s so new, they haven’t even agreed on the name. In this Introduction to Nutrigenomics I will focus on five topics to explain how your genes, your lifestyle and the environment you live in affect your health and wellness.

Topic #1: We all have unique genes. We obtained them from our mother and our father and, ultimately, from all our ancestors. They are the genetic cards that you’ve been dealt and determine who you are.

Topic #2: Some of us get sick and some of us don’t. Some of us age gracefully and some of us don’t. Why?

Topic #3: Our health is influenced by our eating and living habits. But if you think they’re the habits that our genes are accustomed to, read on!

Topic #4: There are many health factors that we can modify — even without genetic information. We discuss what’s important to our heart and circulatory system, our immune system, the detoxification of our bodies and the removal of oxidative stress.

Topic #5: With genetic information we can personalize our nutritional program. That’s the promise of nutrigenomics. The more we know about our genes, the more targeted will be our efforts to improve our health.

Your genes are as deep as it gets. There is nothing that lives underneath them. This is the future we’re living in. Today.

Topic 1. We all have unique genes.
In a book published in the 1950s entitled Biochemical Individuality, University of Texas scientist Roger Williams argued that each of us has a unique body-chemical makeup that makes us respond in different ways to the foods we eat, the drugs we take and the environments we live in. The reason we are unique is that our genes are unique. In fact, the only people born with the exact same genes are identical twins.

We get our genes at the moment of conception from our mother and our father. The collection of all our genes is the reason why we are unique individuals. ‘It is also the reason why we are similar to our biological relatives — our parents and their parents, our children and their children, and most of all our brothers and sisters. Our genetic traits — the color of our eyes, the way we laugh, the diseases we may be susceptible to — are the end-products of our genes and, therefore, tend to be found more frequently in other members of our family than in the population as a whole. Health-care professionals ask you questions about the health of your siblings and parents because their health is relevant to yours.

A gene is the means by which genetic traits are transmitted from your parents to you and from you to your children.

We have 30,000 to 35,000 different genes, by latest count. Each gene is a blueprint for creating one or more proteins. Our body needs thousands of different proteins to perform most of the essential tasks pertaining to the growth, structure, maintenance, integrity and functioning of our physical self. Virtually every cell in our body — from hair to hormones — is either made of proteins or made by them or both.

Almost every cell — and we have literally trillions of cells — contains its own copy of each and every gene. In fact cells contain not one but two copies of each gene: the copy we inherited from our mother and the copy we inherited from our father. These copies may be identical to each other or they may be different. But even if different, they are copies of the same gene because they produce the same protein or set of proteins.

We can’t change our genes — not yet, at any rate. But we can help them do their job and support them so that they, in turn, can support us and help us live a long healthy life. That’s what the exciting new science of nutrigenomics is all about — helping our own unique genes help us live a healthier life.

Topic 2. Some of us get sick and some of us don’t.
Why do some people in their forties get diabetes or heart disease and some people never do? Why do some of us age gracefully and some of us don’t? Why can some people eat junk food all the time and never get sick while other people never eat junk food and get sick all the time? Each person is unique because each person’s genes are different from any other person’s genes. But what does unique mean? How different are we, really?

It is said that every person’s genes are 99.9 % identical to any other person’s genes. That is, only one-tenth of one percent of all the chemical elements that make up our genes are different from the chemical elements that make up another person’s genes.

But some genes have variations. Indeed, as explained in the preceding topic, the two copies of a particular gene embedded in our cells may not be exactly the same. One may be a copy of one variation of the gene and the other a copy of another variation.

By late-2 000, The SNP Consortium of pharmaceutical and other firms had identified 1.4 million genetic variations in the human genome. (SNP, pronounced like snip, stands for single nucleotide polymorphism, which is a scientific description for common genetic variations.) The consortium found that 93% of human genes contain at least one variation. Viewed from that angle, we are indeed very different from each other.

Why do some people in their 40s have heart disease and others don’t? Why do some people age well and some don’t? The answer may be their genetic differences. A lot of scientific research suggests that genes are involved in heart disease and aging.

Remember the Delaney sisters who wrote a book about their first hundred years? A recent study of 137 people 98 years or older who had brothers or sisters 91 to 109 years suggests that aging is related to genetics.

But of course the answer why some people live long lives and age gracefully and some don’t may not be their genes at all. According to the American Heart Association, the number one risk factor linked to heart disease is cigarette smoking. The answer might then be lifestyle. Or someone could be a nonsmoker who grew up in a smoke-filled house because both parents were both heavy smokers and now his wife or her husband is a smoker. Then the answer might be environment.

In most cases the answer is a combination of genes, lifestyle and environment. Most of the common disorders of adult life are thought to have multiple causes — multiple genetic causes and multiple nongenetic ones.

That’s good news. Even if your genes predispose you, say, to heart disease or Alzheimer’s, you can counteract the genetic risk that you were born with by improving your lifestyle and environment.

Topic 3. Our health is influenced by our eating and living habits.
Let’s repeat the good news. The common disorders of adult life and the aging process are associated with certain lifestyles and environments as well as genetic factors. We can’t control the genetic factors, but we don’t have to accept them as if our parents sentenced us to their illnesses without right of parole.

We can try to improve our eating and living habits. Take regular exercise. Help our genes help us live longer and healthier lives. It’s never too late to take an active and informed interest in your future health.

Take nutrition, since we’re talking about nutrigenomics. What should we eat?

We might start with the food pyramid recommendations of the U.S. Government. As adults we are advised to consume 60% of our daily diet (measured in calories) as carbohydrates, 30% as fats (20% unsaturated, 10% saturated) and 10% as proteins. We should eat

• 11 servings of bread, cereal, rice and pasta (down to 8 servings for older adults)
• 3-5 servings of vegetables and 2-4 servings of fruit (down to 2-3 and 2 for older adults)
• 2-3 servings of milk, yogurt and cheese and 2-3 servings of meat, poultry, fish, dry beans, eggs and nuts (down to 3 and 2 for older adults)
• and sparingly of fats, oils and sweets.

Are these recommendations written in stone? Not at all. They have their adherents and they have their critics. They’ve also changed over the years. The current recommendations, made in 1992, are due to be revised in 2005. So how much credibility should we give them?

We might ask our genes. Since we are what they made us, who’s better qualified to tell us? Most of our genes had evolved to their present state by the time the human race emerged as a separate species a half-million years ago — and certainly by what evolutionary biologist Jared Diamond calls our Great Leap Forward 50,000 years ago. In those years we were all hunter- gatherers. But after the end of the last Ice Age 13,000 years ago we learned how to domesticate plants and animals. When people could support themselves through agriculture and animal husbandry, they settled down in villages and gave up the nomadic life of the hunter-gatherer.

But according to anthropologist S. Boyd Eaton, 99.99% of the genes we have today never adapted to agricultural life. They supported the diet and lifestyle of hunter-gatherers and they stayed that way. They never adapted to the diet and_ lifestyle of the agricultural age or the industrial age or the post-industrial age. So, we must ask, what was the diet of hunter-gatherers? Hunter-gatherers ate wild meat, fresh fish, and recently picked vegetables and fruits — and got a lot of exercise keeping the wolf from the door. This Paleolithic Diet, as we now call it, is what our genes evolved to expect over millions of years of evolution, and they haven’t changed. They still expect lean meat, fish, fruit and vegetables. Period.

Roughly 25-30% of the caloric energy intake of hunter-gatherers was consumed as proteins from meat and fish — three times as much protein as the government recommends we take. Another 30-50% was consumed as carbohydrates in the form of wild vegetables and fruits, which provided a lot of fiber. Today we consume many more carbohydrates, mostly as refined sugars and starches and processed grains. Hunter-gatherers consumed fat largely as monosaturated and polyunsaturated fats from game meat, fish and nuts. Our fat is mostly saturated rats from dairy products and red meat and trans fatty acids from processed baked goods and junk food. Hunter- gatherer food contained a lot of omega-3 fatty acids, as from fish, but we eat very little of it. The Paleolithic Diet contained perhaps three times the amount of vitamins and minerals as our diet — and more than our recommended daily allowances. Hunter-gatherers consumed a lot of potassium but little sodium. We consume eight times as much sodium and half as much potassium. Our diets are very different.

When we became farmers instead of hunter-gatherers, we started consuming large amounts of grain, milk and domesticated meat. Most of the diseases associated with this diet are diseases of later life. Since they afflict us after we’ve passed our genes to our children, they were never eliminated by natural selection.

Further changes in our diet came with the Industrial Revolution, when we started routinely refining whole grains, thereby removing much of their nutrition value. That’s also when we started refining sugar. The Industrial Revolution, said one nutritionist, created the greatest feeding experiment ever and nowhere more than in the United States.

The latest change came with the growth of fast food products and restaurants. Now we eat much more processed food than natural food.

But our genes are still adapted for natural food — game meat, fish, vegetables, fruits — and the vigorous efforts required to hunt, catch and collect it. No processed foods. No grain products. No dairy products. Not much saturated fat. Not much time off. No TV.

What do our genes think of our diet? They may have already told us. The current epidemic (as some call it) of obesity manifested itself shortly after the government started publishing food guidelines. Obesity is associated with heart disease and type 2 diabetes.

Topic 4. There are many health factors that we can modify.
The genes we all carry are hunter-gatherer genes, not modern-age genes. They’re old-fashioned, not well adapted to fast processed food or even to the grains, beef and dairy products of an agricultural-age diet. They disapprove of our sedentary lifestyle. What should we be doing to earn their approval and live healthier lives?

The common diseases of adult life and the aging process have lifestyle and environmental causes as well as genetic ones. Nutrigenomics can help you, after you’ve let it read your genes, but there are steps you can take to live a healthier life that apply to all of us. We are, after all, 99.9% similar to everyone else in genetic terms.

A. Your heart and circulatory system would like you to refrain from cigarette smoking since that’s the number one risk factor in heart disease. Other risk factors are high blood cholesterol levels, high blood pressure, obesity and diabetes. These are all common genetic diseases of adult life like heart disease itself  Men are more disposed to heart disease than pre-menopausal women. The risk in women increases significantly after the protective effect of estrogen is lost. Increasing age is a risk factor. Half of all deaths in developed countries are believed to be caused by heart disease.

Vitamins and minerals that may help prevent the onset of heart disease and related conditions are:

B. Your immune system is your personal Defense Department. There is an ages-old arms race between foreign invaders like bacteria adopting new disguises to infiltrate your self-land unnoticed, and your intelligence agents creating new profiles to recognize the invaders and arrest them. If your defense program is not well balanced and supported by fresh resources and a range of nutritional weaponry, it will lower its guard. If lacking sleep or undernourished, it may overreact to relatively innocent visitors and treat them as enemy allergies. It may even confuse your own agents with enemy agents of similar appearance and name — thinking Andy is short for Andropov, for example — and accuse them of being moles and eliminate them. This type of autoimmune response can cause you so much pain, you will think you have rheumatoid arthritis.

To support your immune system, feed it

Arginine, Carotenes, Cobalamin, NAC, Pantothenic acid, Pyridoxine, Selenium, Vitamins A, C, and E and also Zinc

and get plenty of exercise — the immune system relies on your muscles and activity to circulate the lymph that disposes of cell waste.  A healthy skin is also important since that is the first line of defense.  Stress, on the other hand, seems to impair the immune system.  Your immunity will be better if you are less stressed.

C. The detoxification of your body is performed by every cell, but your liver is your toxic dumpster and also your own personal Environmental Protection Agency.  To maintain balance and support your local superfund, feed the liver

Carotenes, Glutathione, NAC, Liponic acid, Selenium, Vitamins A, C, and E and, in a particularly toxic environment, Silymarin and Zinc.

D. Oxidative stress is the result of the normal activity of cells converting food to energy that they need to fulfill their biochemical functions.  The principal stress busters (antioxidants) that neutralize the stress agents (free radicals) are the water-soluble Vitamin C for the blood, the fat-soluble Vitamin E for cell membranes and the blood fats and Glutathione for the cell interiors.

Combat oxidative stress by taking the following nutrients:

Topic 5. With genetic information we can personalize our nutritional program.
Geneticists are discovering more about us every day. Not too long ago they discovered a gene that makes a protein that takes triglycerides circulating in the blood after eating and breaks them down into fatty acids so that they can be absorbed by the muscle and burned as fuel rather than stored as fat. Another gene makes another protein that absorbs blood sugar into the muscle for fuel instead of being absorbed as fat.

Nice genes. Wouldn’t you like to have some?

You do - trillions of them, a pair of each for every cell. They’ve been hanging out in the human genome for untold thousands of years. But they don’t just sit there all day making proteins. In fact, they don’t do anything unless they’re asked. And who asks them`? You do — by exercising. The genes start making their proteins shortly after you become physically active. They stop after about 24 hours of (your) inactivity.

The promise of nutrigenomics (a subdiscipline of genetics) is that the more we know about our genes, the more targeted will be our efforts to improve our health through nutrition. Nutrigenomics takes what we know about health in general, applies knowledge of your particular genes and comes out with a personal nutritional plan tailored to you.

Let’s take an example. There’s a particular gene that makes a protein given the acronym M-SOD that eliminates oxidative stress in a particular type of cell. Or at least that’s what is supposed to happen. But there’s a common variation of the gene — a SNP, which we alluded to in Topic 2, that is described in technical terms in the box below. The variation produces a deformed version of the M-SOD protein that can’t do its job.

Fifty percent of the population - every other person - carries the variation.

But remember we have two copies of this gene, our mother’s and our father’s, and one good M- SOD can do the job by itself. So no problem. Right?  Not for 11% of the population, one of every nine persons. Both copies of the gene they inherited are the variation. Without the ability to create functioning M-SOD proteins, the normal detoxification process that uses M-SOD to remove free radicals and reduce oxidative stress hardly works at all.

That’s where nutrigenomics springs to the rescue. Once we know that you (or I) lack even one copy of the gene that can produce good M-SOD, we may be able to compensate with nutritional supplements to help the cells get rid of the free radical stressors without M-SOD.

That’s the promise of the science of nutrigenomics: To identify common disorders that (1) are associated with genetic processes and (2) are subject to treatment with nutritional formulations and perhaps also lifestyle and environmental changes.

Stay tuned.

Biochemical Individuality by Roger J. Williams (Keats Publishing, 1956)

The Complete Idiot’s Guide to Vitamins and Minerals by Alan H. Pressman and Sheila Buff (Alpha Books, 2nd ed. 2000)

The New York Times Book of Genetics edited by Nicholas Wade (Lyons Press, 2002)

Genome: The Autobiography of’ a Species in 23 Chapters by Matt Ridley (HarperColtins, 2000)

Glutathione: The Ultimate Antioxidant by Alan H. Pressman with Sheila Buff (St. Martin’s Press, 1997)

Guns, Germs, and Steel: The Fates of Human Societies by Jared Diamond (W.W. Norton, 1999)

Neanderthin: Eat Like a Caveman to Achieve a Lean, Strong, Healthy Body by Ray Audette with Troy Gilchrist (St. Martin’s Press, 1999)

Near a Thousand Tables: The History of’ Food by Felipe Fernandez-Armesto (Free Press, 2002)

The Paleo Diet: Lose Weight and Get Healthy by Eating the Food You Were Designed to Eat by Loren Cordain (John Wiley, 2002)