I previously suggested that we should not fear dietary fat. It appears that dietary fat of all types has gotten a bad rap, especially saturated fat. People are sometimes reluctant to increase dietary fat however, because they have heard for decades that "fat was bad," and that they should eat a high-carbohydrate diet for health. I believe the science is gradually correcting itself, and the case against fat is being challenged throughout the world.
Occasionally, I will be discussing nutrition with someone and they proudly tell me how they have gotten over their fear of eating fat. I have lost track of how many times I have heard, "I'm drinking bulletproof coffee!" but then they question why their hunger has not decreased, and they have not lost any weight.
At this point I ask them to take me through a typical day of eating. I am often surprised to hear that while they have increased their dietary fat intake, they have not also reduced their carbohydrate intake. It seems the "healthiness" of whole grains has been imprinted into our minds.
I do not believe you will achieve health benefits from adding dietary fat to a high-carbohydrate diet. In fact, this will likely be counter-productive.
Our goal needs to be reducing our bodies production of insulin. This occurs when carbohydrate intake is reduced. Dietary fat causes minimal to no insulin stimulation, and thus substituting fat for carbohydrates is the goal. We should not be simply adding fat to a high-carbohydrate diet. The most important part of the diet I advocate, and follow myself, is reducing carbohdrates.
When following a properly formulated low-carbohydrate, high-fat diet your hunger will naturally decrease, cravings will subside, and it becomes easy to skip meals. If you attempt this kind of dietary change, and within a few days or weeks you have not noticed these changes, please carefully evaluate your food choices and make sure you are truly eating low carb.
Some foods commonly felt to be healthy but contain high levels of carbohydrates include oatmeal, whole grain bread and beans. These foods must be skipped if your goal is to reduce carbohydrate intake.
If there are foods you are unsure of, please ask me about them in the comment section below and I will be happy to reply with my recommendations.
This is likely to be the most controversial step I am recommending. For the past 30-plus years we have been hearing about the evils of dietary fat in general and of saturated fat in particular. This led to the "low-fat" food craze and a constant barrage of "healthy" low-fat manufactured foods.
Unfortunately, during this time the rates of obesity, type 2 diabetes and cardiovascular disease steadily increased.
What is happening here?
To conduct good science, a researcher develops a hypothesis, but then designs experiments to disprove the hypothesis. If unable to disprove the hypothesis, it stands. This process is notably different than how the nutritional studies that led to the USDA guidelines were conducted. Here the researchers developed a hypothesis but then selectively presented data that would support their hypothesis and excluded all non-supporting data. This is not science. Nina Teicholz presents a well supported indictment of the process that ultimately led to the flawed USDA guidelines in her excellent book "The Big Fat Surprise." I highly recommend reading her book.
In a previous blog posting, I suggested the constant exposure to dietary carbohydrates causes chronically elevated insulin levels which then leads to the chronic diseases of the modern world. It appears the dietary fat recommendations may have contributed to this both directly and indirectly. Because there are only 3 macro nutrients (carbohydrates, proteins, and fats), by reducing fat intake, we must increase the intake of another macronutrient. So clearly, reducing fat intake will lead to relative increases in other macronutrients. Remember the low-fat processed food explosion? Here the industrial food companies often increased sugar content of foods to maintain palatability when fats were eliminated. As a result we ate more carbohydrates as we reduced dietary fats. Because dietary fat leaves the gastrointestinal tract more slowly, increased satiety results. When fat intake is low, our hunger often returns soon after eating, leading to snacking on....more low-fat food products. These are indirect ways reducing dietary fat can be counterproductive.
It also appears the USDA dietary fat recommendations may be contributing to disease directly.
An in-depth discussion of organic chemistry is beyond the scope of this blog posting, however it is important to understand some basic concepts. Dietary fat consists of a chain of carbon atoms. Each carbon atom has the ability to make 4 bonds. If each carbon in the chain has 4 single bonds, the fat is referred to as saturated. If a pair of carbon atoms are linked with a double bond, the fat is called monounsaturated. If multiple carbon atoms are linked by double bonds, it is a polyunsaturated fat. Double bonds are inherently more reactive than single bonds and as we move from saturated, to monounsaturated, to polyunsaturated, the fatty acid becomes increasingly unstable.
Heat, oxygen and light can all damage the carbon chain. This is of particular importance when cooking. Aldehydes and trans-fats can be created by heating polyunsaturated fats. One example of an aldehyde is formaldehyde, a chemical used to preserve biological tissues (remember high school biology class?). Aldehydes are very reactive chemicals and are believed to cause inflammation and oxidative stress to our bodies. This could be a mechanism by which polyunsaturated fat consumption may be contributing to disease.
Traditionally, saturated fats were used for cooking. Once saturated fat was maligned by the USDA, industrially created trans-fats were introduced as a substitute. Unfortunately, trans-fats are now known to be much more detrimental to our health than any naturally occurring fats. Examples include vegetable shortening, and anything that contains the words "partially hydrogenated." Trans-fats raise our LDL cholesterol (bad cholesterol) and reduce our HDL (good cholesterol). These products should be considered poisonous and be completely avoided.
Cooking with polyunsaturated oils became the standard, but as previously discussed, produces harmful byproducts than can cause inflammation, and can contribute to heart disease and even cancer.
Which brings us back to saturated fat. With no double bonds to break, saturated fat tends to be much more stable for cooking. It appears our ancestors already figured this out. Coconut oil is a good example of a cooking oil that is rich in saturated fat. Animal fat tends to be relatively rich in saturated fat as well. Tallow (beef fat) contains about 50% saturated fat, and about 45% monounsaturated fat, the remainder is polyunsaturated. Butter contains about 66% saturated fat, and about 25% monounsaturated fat. These are all good fats to cook with. It is widely known that exercise and moderate alcohol consumption can raise our HDL (good cholesterol). Much less widely known, an even more powerful way to raise your HDL (good cholesterol) is through the consumption of saturated fat. Some people will experience a moderate increase in total cholesterol levels when increasing their consumption of saturated fat. The cardiovascular risk profile will generally be significantly improved, but your individual response should be monitored.
Olive oil contains over 70% monounsaturated fat. Although probably acceptable for low temperature cooking, I recommend buying a high quality brand that is packaged in a dark glass container and consuming it uncooked. It can be poured over cooked food and used on salads liberally. This and other sources of monounsaturated oil like macadamia nuts and avocados should be eaten routinely.
Polyunsaturated fats must be treated carefully. They should not be heated, and only consumed when fresh. 2 main subtypes are referred to as omega 3 and omega 6 fats based on the location of their double bonds. These are essential fatty acids, meaning our bodies can not manufacture them, but requires them for health. The dose needed is relatively low and can easily be obtained through a proper diet. The standard American diet is very high in omega 6 fats, (which tend to cause inflammation) and is often deficient in omega 3 fats, (which tend to reduce inflammation). Once again we are promoting inflammation and chronic disease. We should try to minimize overconsumption of omega 6 fats and seek out fresh sources of omega 3 fats. Excellent sources of omega 3 fats are wild caught salmon, canned sardines, and other seafood. One of the main reasons Americans consume too much omega 6 fat is that soybean oil is ubiquitous and it contains 50% omega 6 polyunsaturated fat. Much of this is partially hydrogenated- which is even worse. Other vegetable oils have infiltrated our manufactured food products and are very difficult to avoid. Please read labels and avoid any foods that contain soybean, corn, sunflower or cottonseed oils.
Because I am recommending a low-carbohydrate, moderate-protein, high-fat diet, most of our calories (50-80%) will be coming from fat. These fats end up becoming incorporated into our cell membranes and will influence how our body functions. We want these fats to be undamaged and to promote health, not lead to inflammation and subsequent chronic diseases. It is important to read labels, avoid harmful fats, and choose the best fats to cook with.
Prior to making a dietary change, I recommend getting a baseline lipid panel. While the vast majority of us will experience a dramatic improvement in our cardiovascular risk profile (increased HDL, decreased triglycerides, decreased body weight, and reduced waist circumference) when choosing to avoid refined carbohydrates and increase dietary fat consumption (as outlined above), our bodies don't all work identically. It is important to monitor your progress and adjust as needed.
I know. I just violated the first rule of weight loss. For decades, we've been told losing weight is as simple as eating less and exercising more. Everyone "knows" this is true. And we all feel bad because we have no willpower and we fail.
This idea is based on the faulty equation: (calories in) - (calories out) = change in body weight. Although thermodynamically it makes sense, biologically it doesn't always. As it turns out, this equation is a gross over-simplification of how our body works. Our bodies have not evolved to shed weight easily.
In addition to pushing highly processed, carbohydrate dense foods, our culture has suggested that we need to spend hours each week on machines doing "cardio" to maintain a healthy body weight. Since most people already do their best to follow the faulty USDA food pyramid, they often focus on lack of exercise to explain their inability to lose weight.
When I gently bring up the idea of losing weight with my patients, almost universally I hear, "I know, I need to get back in the gym..."
Not only do I think exercise as a means to lose weight is unnecessary, particularly in my orthopedic patients, it will very likely be harmful. To take a joint which has been damaged by osteoarthritis and subject it to additional, repetitive, potentially high-impact activity will very likely worsen the symptoms and accelerate the degeneration.
And yet because the large lower extremity joints (hip and knee) experience forces of 3-5 times body weight with every move they make, weight loss can be helpful in reducing pain due to arthritis. Additionally, obesity is an independent risk factor for infection following orthopedic surgery. Worse yet, poorly controlled diabetes has a synergistically negative effect with obesity on infection. Clearly, weight loss is needed. Exercise is not the way to achieve it, however.
My previous posting began to explain how WHAT we eat may be more important than how MUCH we eat. My spontaneous 25 pound weight loss occurred without entering the gym once. As an orthopedic surgeon, I am on my feet all day in the office and in the operating room, and although I consider myself "active", I did not change my activity level at all during my nutritional experiment.
Lets look at the caloric implications of exercise for a moment. A pound of body fat contains 3500 calories of energy. An average person would burn about 500 calories during an hour of jogging. Assuming you could jog for an hour every day of the week, this level of exercise would burn about 3500 calories of fat by the end of the week. If this level of activity were maintained for an entire year, about 50 pounds of body fat would "melt away." Simple. Except for a few biological problems: Appetite is not constant. Basal metabolic rate (the amount of energy you burn at rest) is not constant. Not even highly trained athletes can sustain daily exercise with no rest days and not become injured. And lastly, exercise creates inflammation, which is linked to weight GAIN, and chronic disease.
There is excellent experimental evidence suggesting an increase in appetite and calorie consumption following exercise. The sense of entitlement that often accompanies physical exertion, can undermine proper food selection, because after all, you earned that dessert by running those 5 miles this afternoon. Studies have shown a reduction in basal metabolic rate as well as reduction in non-exercise activity thermogenesis (fidgeting) when energy expenditure exceeds intake. Cardiovascular exercise fueled by carbohydrates generates oxidative stress as sugars are converted to energy in our mitochondria. Additionally, stress hormones like cortisol can be released in response to exercise, and through a variety of pathways cause weight gain. Remember our brains evolved when food was not abundant. If our energy output exceeded intake for long we would not survive. We evolved to conserve energy, and to seek out calories. This probably worked very well historically when food was scarce but has become counterproductive in the modern world where highly processed, palatable, energy dense food is omnipresent. These concepts are further developed and supported in "The Calorie Myth" by Jonathan Bailor.
Please understand that I am not recommending becoming sedentary. I am simply suggesting that we think differently about attempting to use exercise as a means to lose body fat. I recommend remaining active. Take the stairs. Don't look for the closest parking spot. Walk around the block instead of watching TV.
If you really want to lose body fat, I recommend you focus entirely on your diet. I recommend a nutrient dense, low carbohydrate, high fat diet. This does not require calorie counting. You should not feel intense cravings or blood sugar instability. Consider this a longterm/permanent lifestyle change as opposed to a diet- which generally suggests temporary, unpleasant restrictions.
Future postings will explain why I believe this way of eating helps people to lose weight, and why even those who don't need to lose weight should do it anyway. I will also explain how exactly to transition to a well-formulated low carbohydrate, high fat diet, and what you may experience while doing so.
At first glance, it may seem strange for an orthopedic surgeon to be interested in diet. Let me explain how I got here.
Throughout my life I "knew" that fat was bad, whole grains were good, and when people were overweight it was because they ate too much and exercised too little. Simple. Like many people, I did my best to keep a low fat, high carbohydrate diet. I felt guilty when I ate steak, bacon, and ice cream. When I was hungry between meals, I would often snack on pretzels because they contained no fat. When I was thirsty, I would often choose 100% fruit juice.
I remember hearing about the Atkins diet while I was in medical school. This was a diet that involved limiting carbohydrate intake and eating mostly fat. It sounded completely ridiculous to us at the time. Everyone knew that a high fat, low carbohydrate diet was clearly dangerous. I recall a biochemistry lab session where we "proved" eating in such a way offered no metabolic advantage with regard to weight-loss. The explanation was that the diet was so disgusting that people were repulsed by the fat they had to eat and therefore simply ate less.
As a practicing orthopedic surgeon, I see patients with severe arthritis involving knees, hips and shoulders everyday. Since obesity is a risk factor for osteoarthritis of the hips and knees, many of my patients are above an ideal body weight. The knees and hips are subjected to multiple times body weight with every movement and thus losing weight can have a multiplicative effect on reducing joint pain. This is a standard first-line recommendation for joint pain. This was something that we routinely recommend, but rarely occurs.
I routinely evaluate my techniques and results in an attempt to maximize good outcomes, and minimize complications. In the course of doing this, I identified 3 major risk factors linked with orthopedic infections: obesity, diabetes and smoking. This prompted a literature search which revealed that my experience was not unique. The bad news is that a large proportion of our patients had at least one of these risk factors, many had all three. The literature suggests synergy between these factors. This means the negative effects aren't just additive, but may multiply the danger.
Based on this information, I changed my practice immediately. I discussed this information with the local primary care doctors, attempting to enlist their help to keep our patients safe. I feel that each of these risk factors is modifiable. Just as we wouldn't take a patient to the operating room for a total joint replacement if they had active pneumonia, or severe coronary artery disease, we should make every effort to improve these risk factors.
I continued to get a steady stream of patients that had one or more of these risk factors referred to me because they were "ready" for their joint replacement. I then had the challenging and unusual task of explaining that while they may be mentally prepared for surgery, but were not yet medically optimized. Needless to say, patients were often surprised to hear a surgeon talking them out of surgery. An orthopedic infection is generally a big deal, often requiring multiple operations and long-term intravenous antibiotics. Once I explained my concerns to patients, many agreed to try to improve their risk profile.
Stopping smoking can be relatively simple compared to losing weight and controlling diabetes.
We gave examples of the USDA food pyramid, recommended low calorie options, focused on appropriate serving sizes, and offered referral to nutritionists. Several patients became frustrated with me, because they were unable to lose weight. They tried to eat less and exercise more. A common theme was that exercise was impossible due to the arthritis and they could only be hungry for so long until their willpower was exhausted. Some patients decided to find another orthopedic surgeon that didn't care about their risk factors. Some patients decided to undergo bariatric surgery (sleeve gastrectomy) and lost weight rapidly, but this seemed to be an extreme measure to control weight.
One day I was discussing this information with a couple. The husband was rail thin, and his wife (who was here to discuss joint replacement) was very heavy. While explaining my concerns and discussing nutrition with this couple I had a life changing revelation. The husband explained that they both eat the same food, that his wife often ate less than he did, and that he knew that she did not snack or eat secretly because she didn't drive and he did all the food shopping. I suddenly realized something we were never taught.
Different people must process calories differently. And maybe all calories are not equal?
I began researching alternatives to the standard American diet. I came across a very interesting book. "The Big Fat Surprise" by Nina Teicholz. This book alleged that all of what I knew about nutrition, despite my training as a physiology major in college, and medical school was wrong. This prompted me to read yet another book. "Good Calories, Bad Calories" by Gary Taubes. I couldn't get enough. I came across a podcast "Bulletproof Radio" by Dave Asprey. Self-described as a "bio-hacker" this network security expert managed to lose over 100 pounds and keep it off eating a high-calorie, high-fat diet. Since then I have read many thousands of pages and listened to hundreds of hours on diet, nutrition, biochemistry, and exercise. The recurrent message was that carbohydrates aren't as healthy as we think and fat isn't necessarily dangerous. Our modern diet has progressively emphasized processed carbohydrates and excluded dietary fats. While the evidence suggests that Americans are indeed following the recommendations, our difficulty with obesity, diabetes, heart disease, and dementia continues to worsen.
I never had a weight problem. Like most people I had gained a bit of weight since high school, but appeared fit. Nevertheless, I decided to do an experiment on myself. I began a high-fat, low carbohydrate diet. Just like the diet we discredited in medical school. My plan was to try this for 2 weeks. The changes were immediate. I felt much better. I lost 10 pounds and my pants were loose. I decided to extend the experiment for another month. I was so amazed at the results it is now 2 years later and I continue to eat this way. I lost a total of 25 pounds. My waistline shrunk by 3 inches. My body fat percentage is now 10%.
This was awesome, but it gets much better:
I was always mildly hypertensive (high blood pressure), and I had an occasional migraine. By the end of my first 2 week experiment, my blood pressure was perfectly normal. I have not had another migraine since the week before changing my diet. I still have a "type A" personality, but my colleagues have noticed that I am much more relaxed. I have noticed improved mental sharpness, and physical stamina.
Although this experiment was started in secret, the results were immediately obvious to friends, family members, and colleagues. Once I finished reassuring everyone that I was not ill, I then had to explain how dramatically reducing my carbohydrate intake and increasing my fat intake was responsible for my dramatic weight loss.
Even more amazing, is that my weight loss occurred rapidly and without hunger.
I believe there is mounting evidence that the long-term consumption of processed carbohydrates and exclusion of dietary fats is responsible for most of the health problems in western society. Subsequent blog postings will further develop these concepts.