I think low-carb should be the default weight loss diet in America. Not low fat, not calorie-counting with your iPhone app, nor the du jour fad diet of the day. Ditch the carbs, and embrace the fat. And enjoy the benefits!

Before I launch into why I think this way, let me offer a couple of caveats:

Photo by Barbara Dudzińska/iStock / Getty Images

This post does not constitute medical advice. There is no substitute for sitting down with your primary care provider, who can collect the hard data on you (vital signs, physical exam, dietary history, bloodwork, etc), tailor a weight-loss plan that fits you best, and help you wade through the sea of bad information out there.
Everybody is different. I’ll make the case for low-carb as a good default starting point. But it’s not for everybody. The goal of any dietary change is to make that change enjoyable and sustainable. Many people find success with Weight Watchers. Or vegan. I have friends that have achieved great success with My Fitness Pal, or other apps that help you track calorie intake and expenditure. There are many things that factor into which diet will be successful for any one person. Some of these factors reach spiritual or moral planes, like whether or not we should consume animal products. Again, this is where engaging your own primary care provider or weight-loss doctor is so important.

So let’s begin with a true story. It’s October, 2011, and I’m sitting in a conference room in Caesar’s Palace, Las Vegas. I’m attending the annual conference of the American Society of Bariatric Physicians, a community of physicians and other medical providers dedicated to medical weight loss. As Providence would have it, my life and medical career will be changed today by what I’m hearing in this one-hour presentation. The presenter is Dr. Eric Westman, a scientist and physician at Duke University. This is not a lecture. Instead, he is “acting out” a typical counseling session with a new patient in his Lifestyle Medicine Clinic at Duke, which employs low-carb diets to treat obesity, high-cholesterol, and diabetes. And we, the listeners, are the “patient,” stopping him to ask questions, or exclaim “You’re telling me to do what?!” Because he’s saying some pretty provocative things. “Don’t worry about the calories,” he says. “If it’s not on this list I’m giving you, don’t eat it. It’s as simple as that.” “Eat when you’re hungry, stop when you’re full.” “It’s very important that you increase your salt intake.” “If you do this diet, you may be able to come off your insulin within a few days!” And looking down at this list of foods he’s advocating, I see a lot of fat — meat, cheese, sour cream, etc. It’s flying in the face of the orthodox nutrition advice I heard in medical school. Can this be true?

Now step back in time with me a little further, say, to an exam room in my Wednesday afternoon clinic in 2006. I am a resident physician (a family doctor in training), and I’m counseling my patient in weight loss. Again. They are quite frustrated. They say they’ve been following my advice to exercise 30-60 minutes a day. They’ve been avoiding high-fat (and therefore high-calorie) foods. They’ve also been avoiding sweets. They’ve even been allowing themselves to go hungry in order to come in below the 2000 calories per day I prescribed them. Yet they still can’t seem to lose weight. In fact, they continue to gain weight. And their energy level, and hope, are in the toilet. And what is my response? Though I don’t verbalize it, I have a hard time believing them. After all, if they were really following my advice, the pounds would be pouring off, the vitality would be oozing from their pores. I say, “You’ve certainly made some changes. I commend you for that. But you must try harder.” They need to find whatever it is that they’re doing wrong, and they need to stop doing it. Have you, as a person trying to loss weight or lead an overall healthier lifestyle, ever experienced this hopelessness? Have you ever gotten a similar response from your doctor?

At this time in 2006, we were in the middle of the glory days of the Atkins Diet. For a couple of years, millions had adopted this unorthodox eating style, and the pounds were melting off. But we in the medical community were skeptical. We knew that eating “all that fat”, and by extension “all those calories,” could not be good. We felt somewhat justified when a study published in 2005 in the Journal of the American Medical Association demonstrated that the Atkins diet was no more effective than low fat in leading to lasting weight loss (but this study does have a number of flaws). So I did what many doctors did at that time — I blew off Atkins.

Fast forward back to 2011 and Las Vegas. As I sit listening to Dr. Westman, at this conference held by a medical society that’s at the cutting edge of obesity research and practice, I realize that quite possibly all I was was taught in the two weeks of nutrition training I got in medical school was wrong. (That’s right — two weeks to learn the most fundamental science about the human body and hopefully to use nutrition as the most crucial “drug” in any physician’s arsenal! By contrast, my classmates and I spent months being brought up to speed on the latest designer drugs for diabetes and high blood pressure.) Here was a renowned scientist and physician that spoke so convincingly that I felt a like a shade was lifting. I felt that I was heretofore duped by a conspiracy of shoddy science. He brought up a book written recently by Gary Taubes, called Good Calories, Bad Calories, which recounted the long, dubious history of the low-fat hypothesis in America, and the science behind low carb. After the conference, I consumed this 500-page book in about 1 week. And I adopted low-carb for myself. I started eating eggs and bacon for breakfast. I stopped my nightly ritual of shredded wheat and raisons. I packed salad and nuts for work. I lost about 15 pounds. My energy level increased and I slept better. My carpal tunnel syndrome disappeared.

Since 2011, I’ve guided many patients, and even some friends, to low-carb living. And through them I’ve experienced the many benefits of this diet, and not just for weight loss. I’ve seen high triglyceride levels cut in half, diabetes put in remission and medicines stopped, blood pressure normalizing, migraine headaches disappearing, chronic abdominal symptoms melting away. As I currently treat Amish and Mennonite, many of whom place a high priority on what they regard as “natural” medicines to cure disease, low-carb has been a boon for them.

So, why low carb? How does it work? What is the science behind its effectiveness for weight loss? The simple answer is that it targets Enemy Number One in the American obesity crisis — insulin. America’s insulin level is chronically high. Insulin is a hormone made by the pancreas. One of its functions is to help the body regulate it’s blood sugar level. It goes up after you eat a high-carb meal, and then goes down after those carbs are digested. But notice I said “one of its functions.” Another of its functions is to tell your body to store fat. I would say, in light of the current state of obesity in America, it would help us to regard fat storage as insulin’s primary function.

So if the problem is insulin, and insulin is turned on by carb intake, the discussion broadens. The obesity epidemic is not simply one of calorie intake, or exercise. I might not even be about sedentariness. It is a discussion about our culture, about how we make our food (if indeed the food you’re eating was made in a factory), which crops we grow, the involvement of the federal government in writing and advocating for dietary guidelines, and what those guidelines tell us to do. Our current level of carbohydrate intake, and especially our access to highly refined carbs, is unprecedented in the history of our species (whether or not you believe we were created or we evolved). The intake of refined carbs is a phenomenon our bodies are simply not built to handle.

Do you or someone you love suffer from a chronically high insulin level? If so, these might sound familiar:

high blood pressure
abdominal obesity (fat around the waist line, as opposed to other parts of the body)
high triglycerides (one of the numbers on your cholesterol panel)
low HDL (also on your cholesterol panel)
“prediabetes” or diabetes

These five things are the criteria for what doctors call “the metabolic syndrome.” According to the American Heart Association, 20-25% of Americans suffer from the metabolic syndrome! This is evidence that high insulin has reached epidemic proportions. Low-carb greatly improves these five things. But it improves many other things you might not think are related to a high insulin level:

Seizures from epilepsy
Migraine headaches
Obstructive sleep apnea
Hypoglycemia (low blood sugar) after meals
Irritable bowel syndrome
Depression
Polycystic ovary syndrome
Gluten sensitivity

So how can you know if your insulin is high? Well, your doctor can check a fasting insulin level. But there is a simpler way. If you meet many or all of the criteria of the metabolic syndrome above, it’s a good bet that your insulin level is high. You can also get some idea from your last fasting bloodwork (If you happen to have access to it). The following things suggest a chronically high insulin level:

A hemoglobin A1c more than 5.6%.
A fasting glucose (sugar level) over 100.
A triglyceride to HDL ratio more than 2.5. You can find your triglyceride and HDL levels on your cholesterol panel.

When I talk about low carb diets, either with patients, friends, or other health professional, I field a number of very common questions (and objections). To conclude this post, I’ll briefly answer some of those:

"Weight loss is strictly about 'calories in' versus 'calories out.'"

While that statement may be true, and while it no doubt works for many people, nevertheless it is meaningless. That’s like someone saying, “Bill Gates is rich because he made more money than he spent.” And for those of you that swear by the calorie equation, let me suggest that your success may depend more on your diet being low-carb by default than on the calorie count. The problem with “calories in versus calories out” is that (geek warning) we wrongly regard calorie intake as an “independent variable.” In other words, calorie intake is whatever we want it to be (the independent variable), and the consequences just follow (the dependent variable). But is that the case? What if calorie intake is in fact a dependent variable? In other words, what if something is causing us to take in more calories. Take my 4-year-old for instance. He’s a growing boy. Yet my wife and I don’t painstakingly record his calorie intake in order to make sure he comes out positive at the end of the day (so that he grows). He eats like a horse because he’s growing. All we have to do is feed him. It’s hormonal. Now, if you’re reading this, you’re probably older than 4, but I think the principle applies to adults also. You eat more calories than you burn because your body is gaining weight. So the question is — what is telling your body to gain weight? And whatever "it" is, can we silence it? I believe that signal is a hormone. It’s insulin. And yes, we can turn it off by controlling what we put in our mouth.

"All that fat will clog my arteries!"

Not true. You won’t find cow fat, or pig fat, or donut fat in your arteries. What “clogs” our arteries is something called “atherosclerotic plaque.” And the formation of atherosclerotic plaques is way more complicated then simply eating fat.

"Do you really expect me to eat nothing but meat?"

No! That’s a misunderstanding from the faddy (fatty?) days of the Atkins diet. The Atkins diet, and other well-formulated low-carb diets, are high in fat, moderate in protein, and low in carbs. This means that if you only eat T-bones, your high protein intake may short-circuit the beneficial metabolic effects of low carb.

"This will send my cholesterol through the roof!"

The cholesterol in your diet has very little impact on the cholesterol level in your blood. Your cholesterol levels are mostly determined by how much cholesterol, and which kind, your body makes. Skeptical? I challenge you to have your cholesterol tested now, do Atkins for 3 months, then have it tested again. You might be surprised. Typically, triglycerides greatly improve on low carb. HDL typically rises (that’s a good thing). LDL may stay the same or rise a little bit, but this is because your “LDL” number is measuring “good” LDL and “bad” LDL and lumping it in one pile. On low carb, the “good” LDL increases, and “bad” decreases. This may come out in the wash as a slightly higher total LDL. But it has no bearing on your risk of heart disease.

I can say so much more, but I'll keep it to 2000 words. I know that nothing garners more controversy than advocating for a particular diet. Do you disagree with low carb? Or are you sold? Have you experienced success (or failure) with Atkins or other low carb diets? I would love to hear from you. Leave a comment below!

Interested in learning more about low carb?

Talk to your doctor about weight loss and healthy living.
Check out Good Calories, Bad Calories, by Gary Taubes. This is a long book. For a shorter version, try Why we Get Fat, also by Gary Taubes.
Check out the Ancestral Weight Loss Registry and read some of the stories.
Are you an athlete? Check out The Art and Science of Low Carbohydrate Performance, by Stephen Phinney and Jeff Volek.
Like Podcasts and blogs? Check out Livin La Vida Low Carb.

Patrick Rohal, M.D. is a family doctor and the founder of CovenantMD, a Direct Primary Care practice, opening in Lancaster in January, 2016.