Fructose and Liver Damage

Diabetes and obesity-related illnesses are rife in the modern world. What we eat and how much we eat seem to be culprits. Recent research suggests that specifically, too much fructose is a significant problem for the human digestive system. An article from The Economist titled How too much fructose may cause liver damage discusses research in the journal Cell Metabolism.

The article states:

“Specifically, Dr Rabinowitz’s work suggests that fructose, when consumed in large enough quantities, overwhelms the mechanism in the small intestine that has evolved to handle it. This enables it to get into the bloodstream along with other digested molecules and travel to the liver, where some of it is converted into fat. And that is a process which has the potential to cause long-term damage.”

It seems that small amounts of fructose are digested safely. Too much fructose consumption is a problem. If you look around you, you’ll see A LOT of food sweetened with high-fructose corn syrup. Think that might be a problem?

You may also know that fructose is the primary sugar in fruit. So is fruit dangerous? The article doesn’t discuss fruit but I have a couple of thoughts on any potential harm posed by fructose from fruit:

First, my bet is the amount of fructose one would get while eating fruit is far less than one would get while drinking soda or eating processed food sweetened with fructose. Who among us would sit and gorge on fruit? Ever eaten more than one apple or orange? Doesn’t happen very often. (I’d like to meet the person who managed to become unhealthy by eating too much fruit.)

Second, the fiber in the fruit slows the digestion and thus probably slows the release of fructose. That results in less fructose to deal with per unit of time. That dynamic should help make fructose digestion tolerable. In contrast, most fructose-sweetened foods have little to no fiber, (soda and fruit juice are liquids) and thus creates a big turbo-shot of fructose which is something with which the human digestive system doesn’t have much experience. To that point…

Humans haven’t had access to refined sugar until recently in our long history on earth. Fruit is seasonal. It doesn’t sit around for long. In our past, we had to compete with all the other animals in the forest and the jungle to eat the stuff. Either that or it would fall off the tree and rot. Honey, as you know, is guarded by little stinging monsters which makes acquiring that source of sugar a bit costly.

The candy business started in the early 20th century. A hundred years may sound like a long time but in terms of evolution and the human digestive system, it’s an incredibly short amount of time. So our digestive system—a system refined over millennia of natural selection—has suddenly been deluged by sugar. We’re unequipped to deal with this recent development, so we see the problems described above.

” … the conventional wisdom of 3,500 calories less is what it takes to lose a pound of weight is wrong. The body changes as you lose. Interestingly, we also found that the fatter you get, the easier it is to gain weight. An extra 10 calories a day puts more weight onto an obese person than on a thinner one.”

– Dr. Carson C. Chow, MIT mathematician

The New York Times Science section has a fairly interesting conversation with Dr. Carson Chow, an MIT-trained mathematician who works for the National Institutes of Health (NIH) National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). The article is titled A Mathematical Challenge to Obesity. He’s worked with other researchers in applying a mathematical model to help describe and answer questions related to our national obesity epidemic. Several key findings are important to note in addition to the quote at the top of this page:

Also, there’s a time constant that’s an important factor in weight loss. That’s because if you reduce your caloric intake, after a while, your body reaches equilibrium. It actually takes about three years for a dieter to reach their new “steady state.” Our model predicts that if you eat 100 calories fewer a day, in three years you will, on average, lose 10 pounds — if you don’t cheat.

Another finding: Huge variations in your daily food intake will not cause variations in weight, as long as your average food intake over a year is about the same. This is because a person’s body will respond slowly to the food intake.

Dr. Chow was hired to answer the question of what caused the obesity epidemic. He suggests that food overproduction is the culprit. And if we have too much food then we wind up eating too much food. He also says that changing our weight takes a very long time. He says:

Beginning in the 1970s, there was a change in national agricultural policy. Instead of the government paying farmers not to engage in full production, as was the practice, they were encouraged to grow as much food as they could. At the same time, technological changes and the “green revolution” made our farms much more productive. The price of food plummeted, while the number of calories available to the average American grew by about 1,000 a day.

Well, what do people do when there is extra food around? They eat it! This, of course, is a tremendously controversial idea. However, the model shows that increase in food more than explains the increase in weight.

Dr. Chow was asked about practical advice. His answer:

One of the things the numbers have shown us is that weight change, up or down, takes a very, very long time. All diets work. But the reaction time is really slow: on the order of a year.

People don’t wait long enough to see what they are going to stabilize at. So if you drop weight and return to your old eating habits, the time it takes to crawl back to your old weight is something like three years. To help people understand this better, we’ve posted an interactive version of our model at bwsimulator.niddk.nih.gov. People can plug in their information and learn how much they’ll need to reduce their intake and increase their activity to lose. It will also give them a rough sense of how much time it will take to reach the goal. Applied mathematics in action!

Dr. Chow’s final words regarding obesity may come as dreary news for people trying to lose weight and keep it off. He says, “It’s so easy for someone to go out and eat 6,000 calories a day. There’s no magic bullet on this. You simply have to cut calories and be vigilant for the rest of your life.”

That is a very honest observation from a well-trained scientist. Remember that the next time you see an ad for some sure-fire trendy diet or supplement.

Less Sleep = More Eat

A recent study from the Institute of Human Nutrition at Columbia University indicates that lack of sleep contributes to overeating and thus obesity. Here is the conclusion:

The findings of this study link restricted sleep and susceptibility to food stimuli and are consistent with the notion that reduced sleep may lead to greater propensity to overeat.

What’s happening here? Researchers found that, “Overall neuronal activity in response to food stimuli was greater after restricted sleep than after habitual sleep. In addition, a relative increase in brain activity in areas associated with reward… in response to food stimuli, was observed.”

So it seems that sleep restriction caused subjects to like food more. They found it more rewarding. Weird! The take home message is obvious: Get some sleep!

In this study subjects either slept about nine hours or were restricted to only four hours. How much sleep should you get? Ideal sleep time may vary from person to person. WebMD says, “Most adults need seven to eight hours a night for the best amount of sleep, although some people may need as few as five hours or as many as 10 hours of sleep each day.” If you’re a hard-training athlete then you probably need to be on the high side of those numbers.

“The average American now consumes about 2,375 calories per day, about a third more than in the ’70s.” – Time Magazine

Snacking

Two articles may help you understand why so many of us are overweight and why it’s tough to lose the fat. First, Time Magazine gives us Snack Attack! Americans Are Eating More Between Meals. The information here comes from a recent study on Americans’ eating habits over the past 30 years. Among the findings:

“Analyzing data from four nutritional surveys conducted between 1977 and 2006 by the U.S. Department of Agriculture and the Centers for Disease Control and Prevention, the study found that Americans went from eating an average 3.8 meals and snacks a day to 4.9 a day over the last three decades — a 29% increase. The average American now consumes about 2,375 calories per day, about a third more than in the ’70s.”

A lot of this makes sense. Look at our opportunities to eat (another factor examined in the study). We’ve had food in the grocery store checkout for years but now we’ve got food at the Bed Bath & Beyond! I can get candy at Home Depot! I can remember when gas stations had a gumball machine and a cigarette machines–and that was it. Now the average gas station is packed to the gills with weird, low-nutrition/high calorie snack food. Garbage is everywhere and we’re eating it.

Your Brain on Weight Loss

The Huffington Post gives us Weight Loss Psychology: Why Your Brain Might Be Holding You Back. I love this stuff because I’m fascinated by brain function especially at it pertains to exercise. Anyone who’s tried to lose weight has discovered several things. First, everyone knows how to do it: Eat less. Exercise more. Easy? No way! The other thing we’ve all learned is that though weight loss is easy in concept, it’s diabolically difficult to pull off. There’s way more than a simple desire to lose weight. Our short-term pleasure typically wins out over our long-term healthy goals. I like this description of the struggle:

“What drives our behavior is not logic but brain biochemistry, habits and addiction, states of consciousness and what we see people around us doing. We are emotional beings with the ability to rationalize — not rational beings with emotions. If we are stressed, depressed or addicted, no matter how good the advice we are given, chances are that we will not be able to act on it. The more primitive, emotional brain generally has precedence over the newer, more rational brain.”

The article also gives suggestions to help address weight loss:

1.) Focus on a change of heart, not a change of mind. Losing weight through changing what and how much you eat doesn’t happen because you rationally decide to lose weight. You have to have a change of heart; that is, you must get in touch with your deepest, heartfelt desires.Your motivation may not be positive. Indeed, it may stem from a fear of loss. For example, you may not want to get sick. Or you may not want to be ostracized. To get in touch with your motivation, think about the negative consequences of not changing as well as the positive ones. Getting fit must become a priority and your life must be organized accordingly. Nobody can change you but you, and once you’ve made the changes, you need to stay focused. Successful individuals keep their motivation in the forefront of their minds all the time.

2.) Practice self-discipline. Self-control is a muscle that, like other muscles, needs exercise and strengthening. Change doesn’t happen because you want it to happen. Each time you resist temptation, you are developing greater self-control. Success breeds success. Facing down temptations builds strength for future decision moments. Some of my clients throw away their favorite food as a symbolic act that shows they have control over the food and not the other way round.

Self-discipline is required for behavior change, but does that mean that the lack of self-discipline causes obesity? No. That would be like saying aspirin helps a headache go away, so headaches are caused by a lack of aspirin — which is nonsense!

3.) Eliminate or reduce sugary, fat-laden foods. Such foods create physical changes at a cellular level that alter how our brains and bodies react. When analyzing your level of addiction, consider both physical dependence (changes at the cellular level) and psychological dependence (the habitual repetition of a behavior in an attempt to satisfy an emotional need). For example, how often do you use a sugary treat to lift your spirits?

What is often misunderstood is that these dependences exist on a continuum. You can be mildly, moderately or severely dependent, and the degree of dependence determines how difficult it will be to change.

4.) Make history your teacher, not your jailer. You can learn from your mistakes. Instead of [beating yourself up] when you fail to keep your promises to yourself, seek to gain self-knowledge so you won’t repeat the error. No one is perfect. Be sure to acknowledge what you are doing right, not just what isn’t working.

5.) Surround yourself with friends, family and colleagues who will support your effort. Getting fit and losing weight absolutely require others. Although you alone can make the changes you need to make, you can’t make the changes alone. Not only in terms of eating, but in all areas of our lives, we are much more influenced by other people than we imagine. One of the most potent forces for positive change is the emotional support of the individuals who surround you.

You must, however, ask for the support you need. Don’t assume that others know what would be most helpful to you. Similarly, you need to avoid those people who aren’t on the same page as you. Social pressure can work for you or against you. Hang out with the right people.

The Bad News on Fruits & Vegetables

It may not be a huge surprise that most of us in this country don’t eat a healthy diet. Now the data is in and according to the U.S. Centers for Disease Control and Prevention, in 2009, 67.5 percent of adults ate fruit less than two times daily and 73.7 percent ate vegetables less than three times per day. This information comes from an article in Business Week.

These numbers are in contrast to the goals of Healthy People 2010, a comprehensive set of health objectives set by the government. The goals of Healthy People 2010 were for 75 percent of people to eat at least two servings of fruit and 50 percent to eat at least three servings of vegetables every day. Despite these noble efforts, over the past decade there has been a two percent decrease in fruit consumption and no change in the vegetable consumption, researchers found. This program is failing. Why?

It’s hard to imagine that ignorance is driving our avoidance of produce. Who among us doesn’t know that fruits and vegetables are good for us? One issue is that low-income Americans are less likely to have access to fresh fruits and vegetables at affordable prices compared to affluent Americans. (For more on this issue, read about food deserts.)

Connie Diekman, director of university nutrition at Washington University in St Louis discusses the affordability of fresh produce:

“Another factor that seems to impact purchasing fresh produce that is not clear in this report is the cost of fresh produce,” Diekman said. “With economic changes the last several years, the slight differences in consumption based on household income might be an important factor for health-care providers to address.”

(I find it tragically laughable that fresh produce–food that’s plucked right off a tree or a vine; or pulled right out of the ground–can cost more per calorie than a highly complex, laboratory engineered food such as a Twinkie, frozen pizza, or a sugary soda. This is what our farm subsidies are doing to us.)

Most interesting to me are the neurological factors behind what we eat, and why even though we know what’s healthy and unhealthy we still make unhealthy choices. Samantha Heller, a dietitian, nutritionist, exercise physiologist and clinical nutrition coordinator at the Center for Cancer Care at Griffin Hospital in Derby, Connecticut says the following:

“It is easy to fill up on fast food, junk foods, sweets and sugar-sweetened beverages. In addition, by eating these highly palatable foods — those high in fat, sugar and sodium — we alter our taste and mental expectations about how a food is ‘supposed’ to taste.”

“We end up craving these foods and the healthier fare is ignored. Thus, a sweet ripe peach does not taste very sweet to someone who just chugged a 20-ounce soda or ate a bowl of ice cream. The same with vegetables. The delicious taste of many vegetable pales in comparison with high-fat, high-sodium cheese burgers and french fries.”

This is a tremendous uphill battle we face as a nation. It’s this very issue that’s at the heart and core of our health care system. We’ve had heated debate on what form of health care we’ll have and how to fund the system. Yet we avoid the most significant factor in our health care, that is what we chose to eat or not eat. It’s too tough an issue for politicians to discuss as pointing out our failings at personal responsibility tend to anger voters. (In contrast, Michelle Obama has done a very admirable job of bringing attention to the issue of nutrition and obesity.) No number of doctors, drugs, or high-tech medical devices can offset our personal habits. I’m not sure that there’s a light at the end of this tunnel.

Beating Obesity

The latest edition of the Atlantic features an excellent article on our nation’s struggle with obesity. Beating Obesity is written by Marc Ambinder and it’s a thoughtful, in-depth look at the political and social ramifications of this seemingly losing battle. We learn about the major players including First Lady Michelle Obama, the food industry and the insurance companies. (Ambinder himself struggled with obesity and eventually underwent bariatric surgery as a solution.) Ambinder does a very good job in discussing the issues of individual responsibility and the environmental challenges we face such as food at every checkout line (not just at the grocery store), ever growing portion sizes, and junk food that is cheaper than fresh fruits and vegetables.

Most importantly he examines the moral and demographic issues of obesity. He notes the following:

“Black children are more at peril of becoming obese than white children; black women are more than 50 percent more likely to be obese than white women. ‘At the current rate of increase,’ epidemiologists noted in a recent article in Obesity, ‘it will take less than 30 years for all black women to become overweight or obese.’ Obesity rates are above average among Mexican American boys, as they are among Hispanics generally. Obesity rates among young American Indians tend to be nearly twice the national average.

Please check out the article. It’s an excellent piece.

Compulsive Eating is Similar to Drug Addiction

Obesity-related eating issues are in the news again. This time new research indicates that the physiological dynamics of overeating are the same as drug addiction. Compulsive Eating Shares Addictive Biochemical Mechanism With Cocaine, Heroin Abuse, Study Shows comes from Science Daily. The article summarizes a Scripps Research Institute study that was published recently in the journal Nature Neuroscience.

The study examined the brain chemistry of rats that were fed high-fat, high-sugar diets similar to human junk food. The rats quickly became obese and at the same time their brain chemistry showed striking changes. Pleasure centers in their brains changed and became less responsive. The result was the rats had to eat more and more in order to stimulate these regions. These dynamics of food addiction mirror those of rats addicted to cocaine and heroin. Paul J. Kenny, one of the scientists who conducted the study said,

“It presents the most thorough and compelling evidence that drug addiction and obesity are based on the same underlying neurobiological mechanisms. In the study, the animals completely lost control over their eating behavior, the primary hallmark of addiction. They continued to overeat even when they anticipated receiving electric shocks, highlighting just how motivated they were to consume the palatable food.”

A fascinating development in the study came when researchers replaced the junk food with nutritious food: the rats refused to eat. They starved for nearly two weeks after the change.

What seems to be happening to these rats (and likely to obese humans) is that consumption of highly pleasurable food overstimulates and dulls the reward centers of the brain. More food (or drugs) are needed to stimulate feelings of reward and pleasure. Without getting too technical, the neurotransmitter dopamine and it’s receptors in the brain are the key elements here. Dopamine is released in the brain by pleasurable experiences such as drug or food consumption. Consume too much of either and the brain is flooded with dopamine which is essentially bad for dopamine receptors. Over time the brain actually undergoes physical changes and addictive behavior becomes normal and very difficult to change.

The big issue to me is that overeating and obesity are very complex and not at all simple matters of will power. Personal trainers and nutritionists must realize that the brain function of the obese person is very different from the non-obese person. Simply instructing someone to eat differently rarely works and now we know very specifically why.

To that point, I’m skeptical of our various efforts to educate the public on the caloric content in our food (first in NYC and most recently on a national level.) Similarly, it seems that small taxes on soda do little to curb consumption of the sugary junk. Simply putting the information in front of our eyes or enacting a slight monetary penalty isn’t enough and I don’t believe there are many ways government can affect our food choices. (I would be curious though to see the effects of eliminating subsidies for corn, wheat and soybeans. These subsidies keep the price of junk food–which is actually quite complex if you look at the ingredients–artificially low. So this addictive food is also dirt cheap. You and I are paying for this with our taxes!) That said, my hope is that those battling to lose weight won’t give up and resign themselves to poor health by saying “I’m addicted. There’s nothing I can do.”

From what I’ve seen of successful weight loss seems very similar to what I know of overcoming addiction. That is, the individual must decide to make a change for him or herself. Until the individual knowingly makes a firm decision to change no amount of preaching, pushing or cajoling by friends, a spouse, or parents will make the difference. And it is hard work. Perhaps now by recognizing the brain chemistry of over eating we can develop more effective strategies to slim down.

NEAT and the Benefits of Hunger: Part II

Previously we looked at the deliterious health effects of our seated, sedentary modern lifestyle; and we saw remarkable value of NEAT, or Non-Exercise Activity Thermogenesis. Essentially, sitting a lot correlates to early death while moving around a lot makes you healthy–even if this movement isn’t what you might call “exercise.”

Part II of the discussion revolves around the article Movement comes with appetite, found on Science Daily. We’re told of findings by a Swiss research team, whose study is found in the journal Nature. (The full study can be accessed here for a fee.) The science here is fairly complicated so I’m going to try and avoid the overly complex details. Essentially, the star of the study is a molecule found in the liver and hypothalmus called Foxa2. Foxa2 is found in humans and other animals. Here we go with an attempt at explaining why Foxa2 is important.

Foxa2 found in the liver affects fat burning. It’s also found in the hypothalmus which affects daily rhythm, sleep, intake of food and sexual behavior. Researchers also observed that Foxa2 helps form two proteins (MCH and orexin) which trigger both the intake of food and spontaneous movement. Foxa2 is blocked by insulin which is released when we eat. In a fasted state–between meals for instance–insulin is absent and Foxa2 is active. Thus animals tend to be more active while hungry.

If mammals are hungry, they are more alert and physically active. In short, they hunt and look for food. “If you watch a cat or a dog before feeding it, you can see this very clearly,” Markus Stoffel, a professor from the Institute of Molecular Systems Biology at ETH Zurich.

Researchers found a Foxa2 disorder in obese mice. High levels of insulin blunted Foxa2 which in turn reduced production of the two proteins that triggered hunger and movement. To prove this, the researchers bred mice with ultra-active Foxa2 production and the result were mice with high production of the two proteins. These mice lost fatty tissue and formed larger muscles. Their sugar and fat metabolism increased considerably.

The practical suggestion from Stoffel is that we should be hungry sometimes. “The body needs fasting periods to stay healthy.” Hunger promotes movement and thus all the benefits we expect from an active lifestyle. Both the study’s evidence and the suggestions from this researcher are contrary to much of the popular nutrition advice.

The suggestion that one should eat small frequent meals throughout the day (aka grazing) is standard advice found on almost any list (look here, here, here, here and here for starters) of healthy eating tips. I’ve told clients this many times and I’ve followed this bit of common knowledge for years. The reasoning behind the several-small-meals tactic is 1) eating throughout the day keeps the metabolism up, and 2) if we become too hungry then we tend to overeat at mealtime. Is it possible we’ve been doing it wrong? Could three meals a day in fact make us leaner and healthier? I think the answer to that question is the same answer to most questions: It depends. I’ll discuss it more in Part III.

The longer you spend sitting each day, the more likely you are to die an early death — no matter how fit you are.

Right around Thanksgiving I discussed some of the science behind obesity and eating. Now, the tremors of holiday gorging have started, and an eruption of Christmas binging is close at hand. It’s cold outside and here in Colorado we’ve got several inches of snow on the ground. This seems the ideal backdrop to look at obesity again, this time with an eye toward energy expenditure.

Two articles present slightly different information on the same general issue, that is the relationship between movement and obesity. I’ll discuss the first article here and the second in part II of this post. Your Body’s big enemy? You’re sitting on it comes from MSNBC.com. The article has two main topics. First, we’re told of the consequences of our modern, mostly seated lifestyle. We sit at our jobs. We sit getting to our jobs. We sit for entertainment. And our many electronic tools allow us to live our lives while expending very little energy, especially when compared to the bulk of human history which featured far more physical labor than we currently experience. Specifically we’re told about the biochemistry of too much sitting:

“When you sit for an extended period of time, your body starts to shut down at the metabolic level, says Marc Hamilton, Ph.D., associate professor of biomedical sciences at the University of Missouri. When muscles — especially the big ones meant for movement, like those in your legs — are immobile, your circulation slows and you burn fewer calories. Key flab-burning enzymes responsible for breaking down triglycerides (a type of fat) simply start switching off. Sit for a full day and those fat burners plummet by 50 percent, Levine says.”

Sitting increases our risk of diabetes and heart disease and it may even increase our risk for depression. It’s also none too good for our spinal health and posture. A bottom-line assessment of sitting was observed by Canadian researchers: The longer you spend sitting each day, the more likely you are to die an early death — no matter how fit you are. (The article stated this finding but I’m not sure exactly where or by whom this research was done.)

The second topic is NEAT, or Non-Exercise Activity Thermogenesis. (Read more on NEAT from the Mayo Clinic.) Examples of NEAT include tapping our toes, gesturing with our hands while talking, doing house work or yard work, standing while working or any sort of fidgeting–even chewing gum. According to Mayo Clinic research, NEAT has a big impact. A study found that after 10 days, lean participants moved an average of 150 minutes more per day than overweight participants That translates to 350 calories, or about one cheeseburger. Take that out to one month and that’s 10, 500 calories (3 lbs. of fat). In one year NEAT may burn up to 127, 750 calories or almost 37 lbs. of fat!

What can we do with this information? Well it goes to a discussion I’ve had with many of my personal training clients who are trying to lose weight. Find a way to move around somehow. An hour or a half-hour a day in a gym doesn’t add up to much by the end of the week. We’ve got to find ways to move around a lot more than that. Your body needs to move throughout the day. Here are some ideas:

Stand up while talking on the phone.
Set the meeting timer on your Microsoft Outlook (or similar e-mail system) for every half-hour with this message: GET UP. WALK AROUND.
Use the stairs. Avoid elevators and escalators.
Wash dishes by hand.
Quit looking for the parking space closest to the mall or grocery store entrance. Park way back in the back and walk to the entrance.

The bottom line is this: Sitting is death by a thousand keystrokes. Moving yourself about the planet under your own power has tremendous health benefits. Your body doesn’t care if you do it in a gym or whether or not you call it “exercise.”

Alright, you’re done reading. GET ON YOUR FEET AND GO DO SOMETHING!

Drinkers More Physically Active Than Abstainers

Who’da thunk it?? Science Daily reports on a study in the September/October issue of the American Journal of Health Promotion indicates that drinkers exercised more than abstainers–and those who drank more exercised more!

“Among women, those currently using alcohol exercised 7.2 minutes more per week than those who abstained. Relative to abstainers, the more alcohol used, the longer the person exercised. Specifically, light, moderate and heavy drinkers exercised 5.7, 10.1 and 19.9 minutes more per week. Overall, drinking was associated with a 10.1 percent increase in the probability of engaging in vigorous physical activity. The results for men were similar.”

That outcome might be surprising to a lot of people. However, it’s interesting to note that for 2008 Colorado was the leanest state in the nation with an obesity rate of 18.4% yet a recent Men’s Health survey listed Denver as the most dangerously drunk city in the nation.

What does all this mean? It seems we might see parallels between alcohol and medicine. Too much of either will sicken and/or kill us but the right amount might be healthy. It certainly seems clear that some degree of alcohol consumption works well for a lot of people.

In my experience the drinking culture here in the Denver area is one that is strongly balanced with vigorous exercise. Hiking, skiing, kayaking, mountain biking, and/or running is often followed by a loosely reasonable amount of the region’s superb beer. Combine these habits and you get a fairly healthy and happy population.

Denver Fitness Journal

All Things Health and Fitness by Kyle Norman, MS, CSCS, FMS, RRCA Running Coach

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