Tuesday, February 21, 2012

Are all carbs bad?

I eat a lot of carbs: fruits, vegetables, beans and whole grains mostly. I need them to feel full. Some of my friends (and my wife) advocate a low carb, high protein diet, but I have chosen to eat very little meat, cheese and eggs for health reasons. If I give up carbs, that pretty much leaves only fish, of which I eat a lot, but that brings its own health issues.

I 'm clearly not going to lose weight on my chosen regimen, but how bad are carbs really?


The same article I quoted on the dangers of fructose was actually mostly about the dangers of carbs:



Overconsumption of carbs is the primary driving factor for insulin resistance and type 2 diabetes. Unfortunately, the conventional medical wisdom has unwisely been extolling the virtues of carbohydrates for years, even placing them as the "foundation" of the highly flawed food pyramid.

If you are seeking to lose weight and optimize your health, foods like bread, rice and pasta should comprise very low percentages of your diet. Virtually anyone who bought into these high-carb, low-fat dietary recommendations has likely struggled with their weight and health, wondering what they're doing wrong.

The problem is that overeating carbohydrates can prevent a higher percentage of fats from being used for energy, and lead to an increase in fat production and storage. It also raises your insulin levels, which in short order can cause insulin resistance, followed by diabetes. Insulin resistance is also at the heart of virtually every chronic disease known to modern man.

Your Body Stores Excess Carbs as Fat

Your body has a limited capacity to store excess carbohydrates. This is one of the reasons why elevated blood sugar follows their overconsumption. One of the ways your body avoids dangerously elevated blood sugar is through converting those excess carbohydrates into excess body fat primarily in your belly. The way it works is that any carbohydrates not immediately used by your body are stored in the form of glycogen (a long string of glucose molecules linked together). Your body has two storage sites for glycogen: your liver and your muscles. Once the glycogen levels are filled in both your liver and muscles, excess carbohydrates are converted into fat and stored in your adipose, that is, fatty, tissue.

So, although carbohydrates are "fat-free," this is misleading because excess carbohydrates end up as excess fat. Puffed rice, in fact, is capable of making your blood sweeter than white sugar, due to the fact that it is higher on the glycemic index – all the more reason why refined grains are "hidden sugar," and sugar is in many ways "hidden fat."

But that's not the worst of it. Any meal or snack high in carbohydrates will also generate a rapid rise in blood glucose. To adjust for this rapid rise, your pancreas secretes insulin into your bloodstream, which then lowers your levels of blood glucose. The problem is that insulin is essentially a storage hormone, evolved to put aside excess carbohydrate calories in the form of fat in case of future famine. So the insulin that's stimulated by excess carbohydrates aggressively promotes the accumulation of body fat!

In other words, when you eat too much sugar, bread, pasta, and any other grain products, you're essentially sending a hormonal message, via insulin, to your body that says "store more fat." This is actually a highly beneficial response in certain scenarios such as when calories are very scarce. This provides a major survival advantage -- but for nearly everyone reading this, having insufficient calories is not an issue, so this protective mechanism actually sabotages your health.

Additionally, increased insulin levels also:

* Make it virtually impossible for you to use your own stored body fat for energy.
* Suppress two important hormones: glucagon and growth hormone. Glucagon promotes the burning of fat and sugar. Growth hormone is used for muscle development and building new muscle mass.
* Increases hunger: As blood sugar increases following a carbohydrate meal, insulin rises with the eventual result of lower blood sugar. This results in hunger, often only a couple of hours (or less) after the meal, in a vicious endocrine rollercoaster that takes us from meal to compulsive meal without ever feeling satisfied.

So, all in all, the excess carbohydrates in your diet can not only make you fat, they can make sure you stay fat. Cravings, usually for sweets, are frequently part of this cycle, leading you to resort to snacking, often on more carbohydrates. Not eating can make you feel ravenous shaky, moody and ready to "crash." If the problem is chronic, you never get rid of that extra stored fat, and your energy and overall health is adversely affected.


I've cut out rice (except on sushi), potatoes and white bread (mostly.) I've cut back on pastry (although I need to do even better there.) So how am I doing carb wise? Not bad, according to the Harvard School of Public Health:



Don't be misled by fad diets that make blanket pronouncements on the dangers of carbohydrates. They provide the body with fuel it needs for physical activity and for proper organ function, and they are an important part of a healthy diet. But some kinds of carbohydrates are far better than others.

Choose the best sources of carbohydrates—whole grains (the less processed, the better), vegetables, fruits and beans—since they promote good health by delivering vitamins, minerals, fiber, and a host of important phytonutrients. Skip the easily digested refined carbohydrates from refined grains—white bread, white rice, and the like— as well as pastries.

They are pretty positive on fruits as well:



Eating whole grain carbs may actually be good for me:


Study Confirms Health Benefits of Whole Grains

A diet high in whole grain foods is associated with a significantly lower risk of developing cardiovascular disease, including heart disease and stroke, according to an analysis conducted by researchers at Wake Forest University School of Medicine.

“Consuming an average of 2.5 servings of whole grains each day is associated with a 21 percent lower risk of cardiovascular disease compared to consuming only 0.2 servings,” said Philip Mellen, M.D., lead author and an assistant professor of internal medicine. “These findings suggest that we should redouble our efforts to encourage patients to include more of these foods in their diets.”

These results were published on line in Nutrition, Metabolism & Cardiovascular Diseases and will appear in a future print issue.

The findings are based on an analysis of seven studies involving more than 285,000 people. By combining the data from these seven studies, researchers were able to detect effects that may not have shown up in each individual study. The studies were conducted between 1966 and April 2006.

Mellen said the findings are consistent with earlier research, but that despite abundant evidence about the health benefits of whole grains, intake remains low. A nutrition survey conducted between 1999 and 2000 found that only 8 percent of U.S. adults consumed three or more servings of whole grain per day and that 42 percent of adults ate no whole grains on a given day.

“Many consumers and health professionals are unaware of the health benefits of whole grains,” said Mellen.

A grain is “whole” when the entire grain seed is retained: the bran, germ and the endosperm. The bran and germ components are rich in fiber, vitamins, minerals, antioxidants, and healthy fats. These are the parts removed in the refining process, leaving behind the energy-dense but nutrient-poor endosperm portion of the grain. Examples of whole grain foods include wild rice, popcorn, oatmeal, brown rice, barley, wheat berries and flours such as whole wheat.

In addition to protecting against cardiovascular disease, which accounts for one-third of deaths worldwide, there is evidence that whole grains also project against diabetes and other chronic conditions.

“Years ago, scientists hypothesized that the higher rates of chronic diseases we have in the West, including heart disease, are due, in part, to a diet full of processed foods,” Mellen said. “Subsequent studies have born that out – especially with whole grains. Greater whole grain intake is associated with less obesity, diabetes, high blood pressure, and high cholesterol – major factors that increase the risk for heart disease and stroke.”

According to nutritionists, consumers should look for “100 percent whole grain” on food labels or look for specific types of whole-grain flour as the main ingredient, such as “whole wheat.”


Also:


Cardiovascular Disease

Eating whole instead of refined grains substantially lowers total cholesterol, low-density lipoprotein (LDL, or bad) cholesterol, triglycerides, and insulin levels. Any of these changes would be expected to reduce the risk for cardiovascular disease. In the Harvard-based Nurses' Health Study, women who ate 2 to 3 servings of whole-grain products (mostly bread and breakfast cereals) each day were 30 percent less likely to have a heart attack or die from heart disease over a 10-year period than women who ate less than 1 serving per week (1). A recent meta-analysis of seven major studies showed that cardiovascular disease (heart attack, stroke, or the need for a procedure to bypass or open a clogged artery) was 21 percent less likely in people who ate 2.5 or more servings of whole-grain foods a day compared with those who ate less than 2 servings a week (2).

Type 2 Diabetes

In a study of more than 160,000 women whose health and dietary habits were followed for up to 18 years, those who averaged 2 to 3 servings of whole grains a day were 30 percent less likely to have developed type 2 diabetes than those who rarely ate whole grains (3). When the researchers combined these results with those of several other large studies, they found that eating an extra 2 servings of whole grains a day decreased the risk of type 2 diabetes by 21 percent.

Cancer

The data on cancer are mixed, with some studies showing a protective effect and others showing none (4). A large, five-year study among nearly 500,000 men and women suggests that eating whole grains, but not dietary fiber, offers modest protection against colorectal cancer (5, 6).

Digestive Health

By keeping the stool soft and bulky, the fiber in whole grains helps prevent constipation, a common, costly, and aggravating problem. It also helps prevent diverticular disease (the development of tiny pouches inside the colon that are easily irritated and inflamed) by decreasing pressure in the intestines.

Staying Alive

An intriguing report from the Iowa Women's Health Study linked whole-grain consumption with fewer deaths from noncardiac, noncancer causes. Compared with women who rarely or never ate whole-grain foods, those who had at least two or more servings a day were 30 percent less likely to have died from an inflammation-related condition over a 17-year period (7).


and specifically:

1. Brown Rice
2. Oatmeal


My conclusion - I will try even harder to avoid refined grains, but not worry at all about consuming high fiber carbs.

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