Entries in carbohydrates (4)

Saturday
Nov302013

Neurologist David Perlmutter on Brain Dysfunction & Your Daily Bread

"Yes, you read that right: Brain dysfunction starts in your daily bread, and I'm going to prove it. I'll state it again because I realize it sounds absurd: Modern grains are silently destroying your brain. By "modern" I'm not just referring to the refined white flours, pastas, and rice that have already been demonized by the anti-obesity folks; I'm referring to all the grains that so many of us have embraced as being healthful - whole wheat, whole grain, multigrain, seven-grain, live grain, stone-ground, and so on. Basically, I am calling what is arguably our most beloved dietary staple a terrorist group that bullies our most precious organ, the brain. I will demonstrate how fruit and other carbohydrates could be health hazards with far-reaching consequences that not only will wreak physical havoc on your brain, but also will accelerate your body's aging process from the inside out. This isn't science fiction; it's now a documented fact."

Grain Brain: The Surprising Truth About Wheat, Carbs, and Sugar – Your Brain’s Silent Killers

Image credit: Don't Die Early - The Book

Monday
Sep022013

High carbohydrate intake and cognitive impairment in the elderly

An issue of Neurosciences Update published in 2012 by the Mayo Clinic  contains a Research Highlight on the Association Between Macronutrient Intake and Risk of Dementia. The authors studied the 128-item food-frequency questionnaires of 937 cognitively normal elderly, 2oo of which later developed mild cognitive impairment (MCI) or dementia.

Findings showed that among the 937 participants who were cognitively normal at baseline, MCI or dementia developed in 200 and that the risk of either condition was increased in participants with dietary patterns showing a high percentage of carbohydrate intake and reduced in those with a high percentage of fat and protein intake. The authors concluded that a diet high in carbohydrates and low in fats and proteins may increase the risk of MCI or dementia in elderly persons (Roberts et al. J Alzheimer’s Dis. 2012;32[2]:329-39).

The research study, freely available online, does not lists the type of carbohydrates consumed by the participants.  From the food-frequency questionnaires, the authors

… computed the proportion of total daily energy derived from total carbohydrates (% carbohydrate), fat (% fat), and protein (% protein); from carbohydrate components (sugar, non-sugar carbohydrate, fiber); and fat components (polyunsaturated fatty acids [PUFA], monounsaturated fatty acids [MUFA], saturated fats [saturated fats], and trans-fatty acids), and ranked participants by quartiles of intake.

The researchers suggest several mechanisms for the impact of high carbohydrate intake on cognitive function in the elderly, among them:

High carbohydrate and sugar intake may adversely affect cognition through several mechanisms. Hyperglycemia and diabetes may contribute to increased formation of advanced glycation endproducts (AGE), upregulation of the soluble receptors for AGEs, and may generate oxidative stress which in turn, enhances AGE formation. AGEs and oxidative stress have also been associated with greater cognitive decline and with AD through effects on amyloid and tau metabolism.

The increased risk of MCI with lower intake of fats and proteins may involve non-energy related pathways. Fat and protein intake may be required for the integrity of neuronal membranes and fats for the integrity of the myelin sheaths in the brain.

Bottom Line: Don’t let your grandparents skip out on high quality sources of fat and protein.

Wednesday
May252011

Joseph finally quit grains to lower his bad cholesterol

Small, dense LDL is the type of cholesterol that gets under your vascular "skin", the thin lining that protects the inside of the vessel wall. These small, dense molecules are suspected to cause the first insult, which invites other factors to pile on and build a dangerous sludge in your artery called atherosclerosis. If you are a baby boomer like me, you were taught that cholesterol was bad. Then, no, no, HDL cholesterol is actually good; it was LDL cholesterol that was bad. Now we learn there are two types of LDL, large, buoyant LDL and the small, dense LDL. The small, dense version is the worst of the two. 

We also learned that the main cause of elevated cholesterol was fat. Well, yes, factory-made transfat is bad, but the biggest dietary cause of increased small dense LDL, is... carbohydrates! Dr. William Davis, author of The Heart Scan Blog, illustrates this in the case of Joseph, "a whip-smart corporate attorney" with high LDL cholesterol. Joseph's numbers before changing his diet were: LDL - 2620 nmol/L, and small LDL - 2331 nmol/L. Dr. Davis writes:

I advised him to eliminate wheat, cornstarch, and sugars, while limiting other carbohydrate sources, as well. Joseph didn't like this idea very much … (he) replaced all sugar and refined flour products with whole grains, but did not restrict his intake of grains. 

LDL decreased a small amount to 2451 nmol/L and small LDL to 1998 nmol/L. Dr. Davis:

I explained to Joseph that any grain, complex, refined, or simple--will, just like other sugars and carbohydrates, still provoke small LDL. Given the severity of his patterns, I suggested trying again, this time with full elimination of grains. 

Finally, LDL significantly decreased to 1320 nmol/L and small LDL to 646 nmol/L

This is typical of the LDL responses I see with elimination of wheat products on the background of an overall carbohydrate restriction. 

Take home point: Although genetics plays a role, the modern high carb diet with its refined sugars and grains raises your small, dense LDL, the really bad cholesterol. Unfortunately the test for small, dense LDL is expensive and not available in most medical offices. Talk to your doctor and find out what evaluation is right for you. 

(By the way, statin medications do not decrease small, dense LDL.)

Tuesday
Dec212010

Are mainstream nutritionists beginning to recognize the value of Paleolithic nutrition?

Steer clear. Image: KobakoYesterday the Los Angeles Times published an article by Marni Jameson that may nudge the mainstream a tiny step forward to primal nutrition. The article - A reversal on carbs: Fat was once the devil. Now more nutritionists are pointing accusingly at sugar and refined grains - begins thus:

Most people can count calories. Many have a clue about where fat lurks in their diets. However, fewer give carbohydrates much thought, or know why they should.

But a growing number of top nutritional scientists blame excessive carbohydrates — not fat — for America's ills. They say cutting carbohydrates is the key to reversing obesity, heart disease, Type 2 diabetes and hypertension.

Click to read more ...