Category Archives for "Fat & Obesity"

Virus Factor

The Virus Factor: Is there a connection with obesity?

Virus Factor

Wired.com recently detailed the AD-36 virus and it’s correlation with obesity in humans. This discovery is a fascinating tale of its own, as one medical doctor turned fat researcher pursued answers to help his patients.

Dr. Nikhil Dhurandhar followed his father’s footsteps and ran a clinic Mumbai, India to treat overweight and obese patients. Dhurandhar was constantly frustrated that he could not produce answers that would keep his patients from re-gaining weight. “Patients kept coming back,” he recalls.

A serendipitous tea with a family friend and veterinary pathologist gave Dhurandhar a clue that upended his life on a new journey, one might say an obsession.  The pathologist friend was investigating an epidemic in the poultry industry, and something he said sparked a connection in Dhurandhar. The virus causing the illnesses had an interesting symptom–the infected chickens had fat deposited in the abdomen. Could there be a link?

Through several years, a move halfway across the globe, and a healthy dose of skepticism from the research community, Dhurandhar pursued his research, ultimately identifying that a human adenovirus, AD-36, was correlated to higher fat and obesity in humans.

How does a virus lead to fat?

According to Dhurandhar’s research partner, Richard Atkinson, there are three ways that it could:

  • Increased uptake of glucose from the blood
  • Increased creation of fat molecules through fatty acid synthase
  • Creation of more fat cells to hold all the fat by committing stem cells into fat

“So the fat cells that exist are getting bigger, and the body is creating more of them,” says Atkinson.

Read the Wired.com article.

Get the full story in The Secret Life of Fat, now available online and in bookstores.

 

 

 

 

Fat Baby

This little girl couldn’t stop eating, what happened next changed our understanding of fat

Layla appeard to be a healthy newborn. But as she grew into her first year, something changed. Layla would finish a bowl of food and cry until she was given another. Her parents knew this was unusual, but suspected it was a temporary stage of development.

As Layla continued to grow, however, so did her appetite, and before long she was obese. The family tried to reduce her weight gain by cutting calories and encouraging more activity. It was to no avail, because Layla became inventive at finding food. She would burrow through the trash and break into locked cabinets. Once she even forced open a locked freezer and ate frozen fish. Even when they succeeded, limiting Layla’s food intake didn’t help her lose weight, it only served to increase her violent outbursts and her desperate search for food.

Fat BabyDoctors tested her for everything they could think of: a thyroid disorder, pituitary and adrenal glands abnormalities, Cushing’s syndrome, Prader-Willi syndrome, Bardet-Biedl and Alstrom’s syndromes. But all tests were negative. No one was sure what was causing Layla’s ferocious drive to eat and nothing seemed able to stop her.

Layla, it seemed, was destined for a lifetime of obesity.

At about that time, a very interesting study was being conducted that shed light on Layla’s problem. Researchers found that a group of mice with a specific gene mutation had unstoppable eating behavior and grew obese. The mutation was in a gene that made a hormone produced by body fat, and when the mice were given this hormone, they lost weight and not muscle or bone, just fat.

Researches found that this hormone sent the signal to the brain to stop eating. Mice with the gene mutation became obese because they always felt hungry–they never got the signal. Today, we call this hormone leptin and know that it plays a role in humans, as well.

One expert on Layla’s case (Dr. O’Rahilly) learned of this discovery, and he noticed many similarities to the child’s case. Like the mutated mice, she was extraordinarily obese, had an unstoppable urge to eat. He tested Layla’s leptin levels, and found he was correct — Layla was a human version of the mutation, she had no leptin! At last, there was an explanation for why Layla could not stop eating.

What happened next was no less than amazing. When O’Rahilly started administering leptin to Layla, her appetite decreased significantly. As O’Rahilly recalls, “She was eating a quarter compared to what she was normally eating. She went from being a completely focused eating machine into a normal kid.”

Further research would show that leptin not only reduces appetite but is also involved in metabolism. In addition to eating like gluttons, mice without leptin tend to move less and burn less fat. Without leptin, Layla was unable to burn fat normally, which is why even when her calories were restricted she could not lose weight.

Hormones matter much more to our weight and metabolism than we often give them credit. Before starting a diet it’s important to understand how our hormones really work. Here’s one example why: High fructose foods reduce the effect of leptin, and can lead to leptin resistance. With leptin resistance we are more hungry and gain weight.

There are many things you can do to promote fat-burning hormones such as growth hormone and testosterone and decrease the effects of fat-hoarding ones such as insulin. I discuss all of this at length in my book, The Secret Life of Fat.

Elements of a Paleo diet

One reason why Paleo doesn’t work for everyone (and how to burn stubborn fat)

Based on the fact that humans have only recently undergone massive changes to our diets, the paleo diet cuts the refined sugars, grains, and legumes most of us now eat in abundance, but which our bodies aren’t suited for. It’s a diet that works wonders for many people, but there are a certain few for whom paleo doesn’t live up to its expectations. So if paleo is fundamental to our human core, why would it work for some but not for others?

Elements of a Paleo diet

Elements of a Paleo diet

One issue lies right in the theoretical basis of the paleo diet — our DNA. Humans grow and adapt to our environment. We experience variations in our genetic code that alter us over time, and they are not the same for everyone. So whatever genetics our ancestors had a few thousand years ago, they are not necessarily what we all still carry today. Some variations make it easier or harder to see results with the Paleo diet, or any diet plan.

Once we account for some of these variations, however, Paleo can work again.

One issue lies right in the theoretical
basis of the paleo diet — our DNA.

Take for example recently identified genetic variation known as FTO. An FTO variant has been shown to increase desire for energy rich fattening foods. An appetite for high calories foods is bad enough, but this FTO variant also leads to another outcome — it creates more fat cells! A study at MIT showed that those with the FTO variant gene also create more white fat cells (those which hoard fat) than brown fat cells (those which burn energy to produce body heat). So the net effect of the FTO alteration is a larger appetite and a higher propensity to create white fat cells. It’s a combination that would make it hard for anyone to lose weight!

Our genes are changing on an ongoing basis. And for the last few centuries that we’ve had farming and industrialized food our genes and bodies have changed further. Paleo is a sound and sensible approach for most. But if you find paleo isn’t quite working for you, the answer may be in your genes.

Fortunately, researches who study obesity genes say that exercise doesn’t just combat fat but also the effects of “fat” genes. For instance, research at Mt. Sinai in New York showed that 30 minutes of activity 5 days per week reduced the effect of the FTO variant by 27%. Dr. Ruth Loos, the lead researcher of the study, mentions that the exercise “doesn’t have to be overly vigorous, as long as you start to sweat,” which means even biking, gardening, or going for a brisk walk will work. Of course, that still leaves 73% of the gene’s effect intact. To ratchet up the fight, research at Pennington Biomedical Research Center in Louisiana showed that more intense activity will blast through genetic predisposition to fat. It seems that once we enter a specific range of exercise, the body kicks in to lose fat no matter what our genes want.

But that’s just exercise, fasting is another way to burn stubborn fat. Fasting will induce growth hormone (which peaks at night) and amplify your fat burning pathways. Extend the overnight fasting period from 5 pm to 11 AM the next day to increase growth hormone production and fat burning.

You should also look to remove obesogens from your diet — these foods mimic estrogens and can lead more fat. They are found in plastics, pesticides, and preservatives and even some plants such as flax and soy. You could be following the paleo diet to a T, but if you’re exposed to obesogens your chances of maintaining fat are much higher.

The Secret Life of Fat

Stubborn fat is a reality for many. You may have biological reasons why you don’t lose weight as quickly as your neighbor. However, you can make almost any diet successful, as long as you understand your fat first — including all the ways we get fat and how fat fights to stay on us. I explain all the unknown facts about fat in The Secret Life of Fat.

Bones

What would happen if we had no body fat?

We willingly spend billions of dollars to win the war on body fat every year, and yet it always seems to come back, and more resilient than ever. Why is that? Why is that fat just keeps fighting back? Because as much as you think you want to lose fat, your body still isn’t convinced it should.

Benefits of FatThere are good reasons for your body to accumulate and store fat. Fat is a cushion of energy in times when we go too long without eating. It’s the safety net that keeps your heart, brain, and muscles going when we need more fuel than what’s immediately available.

But more than just a reserve of calories, fat plays a critical role in many body functions because it releases hormones. This discovery, in the 1990s, led fat to be reclassified as an endocrine organ. It turns out fat does some great things for us, though we don’t normally recognize them. What does fat do for us?

Enables Puberty — Ballerinas, who are often super skinny due to their strict lifestyle, will miss their periods or even delay puberty until after ending their career. This puzzled doctors and scientists until they found that fat makes both estrogen and leptin which are needed for puberty and reproduction.

Strengthens Our Bones — Fat isn’t just important for puberty, it’s also important for our bones. It turns out that body weight is a better predictor of bone mineral density, a measure of fracture risk, than age.

Boosts Our Brain Size — The health of our fat (yes, your fat can be sick or healthy!) affects our brain size. Patients with defective fat (fat that’s doesn’t make sufficient hormones) have smaller brains. Individuals with anorexia, who are characterized by having minimal fat, also see a decrease in brain size and volume. On the other hand, people with too much visceral fat are at risk of dementia. The health of our fat is directly connected to the health of our brain!

Enhances Our Immune System — On top of cushioning our most sensitive organs and keeping us warm, fat (through leptin) also strengthens our immune system and assists in wound healing. In fact, anorexics have weaker immune systems and heal more slowly than those with normal fat levels.

Helps us live longer — In times of sickness a little extra fat may prove beneficial. For instance, while fat has been blamed for heart attacks, strokes, diabetes, and a host of other serious illnesses, researchers are finding that low fat levels may make us even more vulnerable to death from those conditions. In many studies, being overweight actually lowers mortality from disease!

Without body fat, life as we know it wouldn’t exist. Perhaps fat is not quite the enemy we always make it out to be. At the very least, it is certainly more complex than the typical one-size-fits-all diet makes it out to be.

Yes sumo wrestlers are obese — but are they unhealthy?

By any standard, the sumo wrestler would be considered obese. Sumo wrestlers weigh in the range of three hundred to four hundred pounds and ingest 5000 to 7000 calories a day, including a lot of fried food. While their diet is low in processed foods and sugar no one could argue that their diet is healthy.

And yet they don’t suffer from afflictions normally associated with obesity. Their plasma glucose and triglyceride levels are normal. Even their cholesterol levels are low. How is it that they can escape the health effects of excess weight in ways the rest of us can’t?

The question puzzled doctors for years, until a study using computer tomography imaging looked at the fat deposits on sumo wrestlers. The study revealed that although the wrestlers have enormous bellies, most of their abdominal fat is stored immediately under the skin, and not behind the stomach wall within the gut or visceral area. In fact, sumo wrestlers had about half of the visceral fat of regular people with visceral obesity.

This fat distribution is crucial to understanding body fat and health. While sumo wrestlers are not what comes to mind when we think of fit athletes, their training routines are quite intense. In fact, sumo wrestlers are only protected from health risks so long as they continue their intense training. When sumo wrestlers retire and veer away from their exercise program, they almost immediately develop more visceral fat and the classic problems of obesity such as high levels of insulin, insulin resistance, and diabetes.

Evidently, the sumo’s physical exercise and diet low in sugar helps him to avoid visceral fat. So how can strenuous activity prevent sumo wrestlers from getting obesity-related ailments?

Exercise has been shown to increase adiponectin levels. This hormone sensitizes the body’s response to insulin, and guides glucose and fat molecules out of our bloodstream and into body fat, where they belong. This is important because an excess of circulating glucose and fats in the blood are precursors for diabetes and metabolic disease. It also removes from circulation toxic lipids known as ceramides, which contribute to insulin resistance, inflammation, and cell death!

The sumo’s intense physical regimen (and the release of adiponectin) enables fat to be stored in the periphery instead of in the visceral area. And when the sumo curtails this exercise regimen, unhealthy visceral fat quickly accumulates.

The tale of the sumo wrestler is just one of many that I write about in The Secret Life of Fat showing the complex interactions that occur in our bodies which are rarely covered in one-size-fits-all diet books. Whether you’re looking to lose weight or learn more about one of the bodies most mysterious organs, follow along as I expose fat!