Really, you don’t need carbohydrates

I keep running across comments like this one, from “Ending the Food Fight,” by David Ludwig, MD, PhD: “[Low carb diets] do produce more weight loss than low-fat diets, but only temporarily.  After one year, people following both diets gain back nearly all of the weight they lose.  These approaches ultimately fail because our bodies and our minds rebel against severe restriction of any major nutrient, whether fat or carbohydrate.  (How long do you want to keep eating that bacon double cheeseburger, hold the bun, thank you?)”

First off, I assume Dr. Ludwig is referring to people who stop eating low carb and then gain back their weight, which of course, they will.   Continuing to eat low carb at the level of carbohydrates your body can handle, which might be 20, 50, or 100 grams a day, is one of the most successful ways to maintain weight loss.

Second, why does Dr. Ludwig assume that all macronutrients (fat, protein, carbohydrate) are equal, or equally required?  They’re not.  Carbohydrates in the form of agricultural grains did not even exist in the human diet until several thousand years ago.  People who eat a “Paleo/Primal” or “Caveman” diet eschew all grains, legumes, and dairy.  They eat mostly vegetables and meats, and a small amount of fruit.  (Modern fruit is larger, sweeter, and available for more of the year than ancient fruit).

It’s maybe not surprising then, given that they are so new, that carbohydrate is the only macronutrient your body does NOT require.  It can get along just fine on zero carbohydrate, unlike fat or protein.  “…animal foods contain all of the essential amino acids (the basic structural building blocks of proteins), and they do so in the ratios that maximize their utility to humans.* 94 They also contain twelve of the thirteen essential vitamins in large quantities…The thirteenth vitamin, vitamin C, ascorbic acid, has long been the point of contention. It is contained in animal foods in such small quantities that nutritionists have considered it insufficient and the question is whether this quantity is indeed sufficient for good health.”

Taubes, Gary (2007-09-25). Good Calories, Bad Calories (Kindle Locations 6551-6557). Random House, Inc.. Kindle Edition.

 It turns out that the tiny quantity of vitamin C in animal foods is sufficient, provided you aren’t eating a diet high in carbohydrate.  In other words, you only need to supplement the vitamin C available from animal foods if you eat a lot of non-animal foods.

Taubes, Gary (2007-09-25). Good Calories, Bad Calories (Kindle Location 6630). Random House, Inc.. Kindle Edition.

Another argument you sometimes hear is that dietary carbohydrates are required to provide glucose for the brain.  But this is not so.  The liver manufactures the fuel it needs from other nutrients if dietary carbohydrate falls below a certain level.

Taubes, Gary (2007-09-25). Good Calories, Bad Calories (Kindle Locations 6492-6498). Random House, Inc.. Kindle Edition.

And what about Dr. Ludwig’s opinion that people can’t live forever without the hamburger bun?  A great effect of a low carb eating plan is that the desire for carbohydrates greatly diminishes, or disappears altogether.  And in sensitive individuals, eating the bun after getting used to the low carb style will probably make you feel sick and tired.  Go ahead and try it once, like Juliana did with a scoop of ice cream, and you won’t be so tempted the next time.

Dr. Ludwig instead advocates a low-glycemic diet, which I bet works better than a low fat diet for many people.  But in sensitive individuals like Juliana it would not work because it includes more fruit and grains (even if they are whole grains!) than her system can handle.

We check in with the Packard Program

Juliana and I visited with the staff from the Packard Program yesterday.  They are doing great good in the world trying to help obese kids achieve a healthy weight, and they have good success.  Nonetheless, I believe that the calories in/calories out model that underlies the program is wrong.  So why does it work as well it as it does?

The Packard Program teaches kids to substitute lower-calorie yellow or green foods for higher-calorie red foods.  In many cases, those substitutions are from super-high-carb foods to less-high-carb foods.

From a glass of apple juice, for example, to an apple.  8 ounces of apple juice has about 29 grams of carbs; one medium apple has about 16 grams of carbs and it also has 4 grams of fiber, for only 12 grams of “net carbs.”  (When counting carbs, you subtract the fiber grams from the total carbohydrate grams, because fiber does not provoke the same insulin response).

Or from a high-sugar cereal to a low-sugar cereal.   Changing from raisin bran (36 grams of net carbs per cup) to cheerios (19 grams of net carbs per cup) cuts the carb load almost in half.

Both those substitutions are lower calorie changes, but they are also lower-carb changes.  So is it the carbs, or the calories?   I think it’s the carbs.  See chapters 19 and 20 of Gary Taubes‘ “Good Calories, Bad Calories” for a full discussion of this point.

The real power of the realization that carbohydrate restriction is the most important part of the eating plan is that your child will not be constantly hungry on a low carb plan, as they will be on a low calorie “balanced” plan.  At Packard yesterday I really emphasized this point:  Juliana complied perfectly with the program and did lose 6 pounds in 10 weeks.  But she was hungry all the time and I didn’t see how she could possibly keep it up.

A low carb eating plan doesn’t require superhuman restraint to follow.  That makes it a lot easier to coach your child on a low carb eating plan than a low calorie eating plan.

After losing a lot of weight in the beginning, Juliana’s weight loss rate has slowed on the low carb eating plan.  But even if she only loses an average of a 1/2 pound a week, as she did on the Packard Program, she will eventually get to her goal weight WITHOUT suffering constant hunger.  And in the meanwhile, her energy level is high, she has a completely new level of physical stamina, and her mood is consistently good.

NOW I see why she’s always tired and hungry

Everything Taubes wrote made sense when I thought about Juliana’s history.  Juliana’s ability, at the age of four, to eat enormous quantities of pasta and be hungry two hours later was explained.  Her obvious preference for simple carbohydrate foods–bread, pasta, baked goods of all kinds–and her difficulty controlling her intake of such foods was not a lack of willpower but a normal response to the hormonal signals her body was sending.  Her frequent lethargy, from a young age.  Her constant hunger on the Packard program made sense.

When I ate a vegetarian diet, I was heavier

As a former, 18-year vegetarian, the information about carbohydrates was very surprising. Being a vegetarian entails eating even more carbohydrates than an omnivore, and I considered that eating plan to be super healthy. When I thought back, however, I realized that I had generally been heavier as a vegetarian than I was as an omnivore. I weighed more in college than I did after having three children.

I thought about our efforts on the Packard program. Juliana and I had gone heavily into a plant-based eating plan as a way of eliminating reds. We ate a lot of bean soups, with a small amount of meat for flavoring. I went even further in that direction then Juliana, adopting an “Eat to Live” style diet in which one eats mountains of vegetables and fruit.

I also, in accordance with the red/yellow/green system, stopped eating any dessert.  I lost 3 or 4 pounds over a month. I had noticed that while I was satisfied enough after eating a mountain of vegetables, I really, really craved the whole wheat pita bread with lowfat cheese I had alongside it.  It wasn’t a particularly yummy carb, whole wheat pita bread, but my body was acting like it was chocolate cake.  Hmmm…what was it about carbs?

Her grandfather had type II diabetes

I also remembered that Juliana’s grandfather, although healthy overall and not overweight when I knew him (he had been heavier when he was younger), developed diabetes in his 70’s, a few years before he died.  He was able to control it without medication by limiting his carbohydrate intake to less than 200 grams a day.

Type 2 diabetes doesn’t just appear overnight–it’s the end result of an ongoing process.  A person is classified as diabetic when their insulin response crosses a certain threshold.  But before it crosses that threshold it’s been approaching it for years.  And the stimulus that creates the insulin reaction is carbohydrate.

Juliana’s grandfather’s diabetes was a further clue that Juliana could be predisposed to carbohydrate sensitivity.  The effect of carbohydrate sensitivity is more insulin production in the body for the same amount of carbohydrate relative to a non-sensitive individual.  More insulin production causes weight gain.   If you or your child’s other parent is overweight, or his or her siblings or parents; or your siblings or parents; or if there is type 2 diabetes in either family even if no one is overweight, these are further indications that your child may have a low tolerance for carbohydrates.

In Overeater’s Anonymous, they eat no flour

Around the same time I talked to a friend who was doing the Over Eaters Anonymous program.  She said she ate nothing with the word flour in it, and in talking to her it was clear that she ate few grains overall.  She said that in OA they talk about being “in the sugar,” where one is craving carbohydrate rich foods and can’t stop eating them.

I have 3 kids but only 1 is overweight

Taubes‘ books also explained why, although I had 3 children who were offered the same food, only one of them was overweight.  They explained why a child could be overweight even while eating the recommended 5 to 9 servings of vegetables and fruit a day.  While not drinking soda, juice, or even milk–just water.  While not eating fast food.  While virtually never eating out at all.  While rarely eating dessert. While being physically active.

Insulin: The Fat Storage Hormone

Gary Taubes explains that in any basic biology textbook, insulin is known as the fat storage hormone.  Its job is to direct your fat cells to store energy as fat.  If you produce more insulin than your neighbor from ingesting the same amount of food, you will also store more of that food energy as fat.

Carbohydrate provokes the release of insulin, in some individuals more insulin than in others for the same amount of carbohydrate.  That is why two people can eat the same food and exercise the same amount and one can gain weight while the other doesn’t.

It gets worse.  Call the weight gainer Jim and the weight maintainer Steve.  Jim will be hungry sooner than Steve.  Why?  Most or all of the energy in the food Jim just ate will have been tidily stored away in fat cells, instead of being available for Jim to use.  Jim will feel hungry again in response to the lack of energy.

Jim will also feel tired, because the food energy has been sequestered in fat cells rather than remaining available for use.

Protein and fat do not provoke insulin production to nearly the same extent as carbohydrate.  The energy that is eaten is not stored as fat; it remains available for use.  Controlling insulin production is the key to better energy and a healthy weight.  And the key to controlling insulin production is controlling carbohydrate intake.

Taubes concludes that the logical eating plan for weight control (and a host of other health benefits I haven’t described here) is one that limits carbohydrates to much lower levels than the USDA-approved Standard American Diet.

Low fat, high carb eating has made us fat.

The low fat, high carb diet that public health authorities began recommending in the 1980s was supposed to be relatively low in calories, and therefore help people achieve or maintain a healthy weight.  Carbohydrates have fewer calories per gram of weight (4) than fat (9) and the same as protein (4).  Consuming more carbohydrates than protein or fat was supposed to supply fewer overall calories in the diet and result in a healthy weight.  But that’s not what happened.  Instead, people have gotten fatter and fatter.

Public health authorities now blame the obesity epidemic on the public not following their advice.  Gary Taubesargues that they have followed the advice, and cites food consumption statistics to back this up:

“Consider, for instance, that most reliable evidence suggests that Americans have indeed made a conscious effort to eat less fat, and particularly less saturated fat, since the 1960s. According to the USDA, we have been eating less red meat, fewer eggs, and more poultry and fish; our average fat intake has dropped from 45 percent of total calories to less than 35 percent”

Taubes, Gary (2007-09-25). Good Calories, Bad Calories (Kindle Locations 219-222). Random House, Inc.. Kindle Edition.

Yet people, including children, have become fatter than ever:

“The prevalence of overweight in children six to eleven years old more than doubled between 1980 and 2000; it tripled in children aged eleven to nineteen.”

Taubes, Gary (2007-09-25). Good Calories, Bad Calories (Kindle Locations 4765-4766). Random House, Inc.. Kindle Edition.

Why is the high carb, low fat dietary advice just plain wrong?  Because it ignores what different types of foods do in the human body.  Carbohydrates produce a different biological response than do fats or proteins.  Specifically, they produce a response that stores food energy as fat.  Fat and protein do not.  However, the energy from fat and protein, if eaten in conjunction with carbohydrate, will be swept up in the same process and stored as fat.  Eating fat and protein with too much carbohydrate (and for many individuals, “too much” is a very small amount), will make you fat.

Calories In/Calories Out–NOT

The calories in/calories out model of weight management says: burn more calories than you consume to lose weight; –balance calorie consumption with expenditure to maintain weight.  Like the public health ad said that I remember from the Washington subway in the late 90’s:  switch from mayonnaise to mustard on your daily sandwich and lose 10.4 pounds a year (savings of 100 calories/day for 365 days).  The CDC recommends that children get 60 minutes of moderate intensity physical activity on most days of the week, and preferably every day.  For a 154 pound person, they estimate that 60 minutes of brisk walking (4.5 mph) will burn 460 calories an hour (more if you are heavier, less if you are lighter).  That’s 3220 calories per week, or 47.8 pounds of expected weight loss over a year.

Virtually all of the dietary advice provided to parents who are trying to help their children achieve or maintain a healthy weight conforms to this model, the most recent and visible example being Michelle Obama’s Let’s Move initiative, which is closely tied to the USDA’s new food plate eating plan, and replaced the earlier pyramid eating plan.  Both the new Food Plate and the old Pyramid are high carb, low fat eating plans.

These diets were recommended by public health authorities beginning in the 1980s because it was believed such a diet was beneficial for preventing heart disease, while at the same time controlling weight because it was supposed to be a relatively low calorie diet.  Carbohydrates have fewer calories per gram of weight (4) than fat (9) and the same as protein (4).  It was further thought that even if the diet itself didn’t turn out to be protective against heart disease, it would control weight, and controlling weight would be protective against heart disease.

There’s just one problem:  high carb, low fat diets like the new food plate and the old pyramid don’t work for weight loss or weight maintenance and don’t improve other health markers either.   Gary Taubes, in the lengthy “Good Calories, Bad Calories,” and the cliffs notes version “Why We Get Fat and What to do About it,” eviscerates the logic behind low fat, high carb diets.  Reading these books completely changed how I thought about Juliana’s struggle with weight.   If you eat like the USDA pyramid and are a normal weight, your body can handle a high level of carbohydrates (for now at least)–the evidence for that is that you are a normal weight.  Your child can’t, and that is why he or she is overweight.

If you are a normal weight adult trying to help an overweight child, you should run to the library or bookstore for these books.