Category Archives: Grains

May 25, 2019 · 5:20 PM

A Whole Grain Food Isn’t What You Think

Now THIS is whole grain

Do you know what a whole grain food is? I thought I did. I was wrong. Here’s the definition in a 2013 article in Scientific American:

The term “whole grain” might evoke an image of a whole, intact grain—that is, a fiber-rich coating of bran surrounding a starchy endosperm and a small reproductive kernel known as the germ. But in a definition created in 1999 by the American Association of Cereal Chemists (AACC) International, an organization of food industry professionals and scientists, and adopted by the U.S. Food and Drug Administration in 2006, “whole grain” refers to any mixture of bran, endosperm and germ in the proportions one would expect to see in an intact grain—yet the grains can be, and usually are, processed so that the three parts are separated and ground before being incorporated into foods. (Refined grains, on the other hand, are grains that have been stripped of their bran and germ.) For a food product to be considered whole grain, the FDA saysit must contain at least 51 percent of whole grains by weight. Compared with intact grains, though, processed whole grains often have lower fiber and nutrient levels.

Many of the scientific studies that support the healthfulness of whole grains, and there aren’t many, considered wheat germ and bran cereals as whole grain foods. But those are only parts of a whole grain. The studies that linked lower heart disease and type 2 diabetes with whole grain consumption were diets high in fiber or bran as a whole grain.

Read the whole article (it’s not long) to find out how modern processing of whole grains can reduce their healthfulness.

Food companies lump ground whole grains, partially processed grains and intact unprocessed grains together under the same broad category of “whole grains,” so it’s difficult for consumers to know which they’re getting.

Click pic to buy book at Amazon.com in the U.S.

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October 4, 2014 · 2:00 AM

Low-Fat Diet Loses to Mediterranean Diet in Heart Disease Prevention

The American Journal of Medicine has an article entitled “Diets to Prevent Coronary Heart Disease 1957- 2013: What Have We Learned?” The authors conclude:

The Mediterranean-style diet, with a focus on vegetables, fruit, fish, whole grains and olive oil, has proven to reduce cardiovascular events to a degree greater than low fat diets, and equal to or greater than the benefit observed in statin trials.

The only bone I’ll pick with that quote today is that folks with diabetes and prediabetes often have unacceptable blood sugar spikes when they eat whole grains. That’s one reason I designed the Low-Carb Mediterranean Diet.

Steve Parker, M.D.

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July 24, 2012 · 2:00 AM

Sources of Calories in U.S. Diet Over Last Four Decades

Italian seaside totally unrelated to this post

Do you ever wonder how many of your total calories come from added sugars? Grains? Dairy products? Added fats?

Deriving your personal numbers would require detailed nutrient analysis, but if you’d like U.S. averages, see this cool infographic at Civil Eats.

It also shows how many calories are or were available for consumption per capita over time (without accounting for wastage in restaurants). It’s based on U.S. Department of Agriculture data.

A superficial glance suggests that U.S. per capita daily calorie consumption has increased by about 600 from the 1970s until now. But remember, these numbers don’t discount for restaurant wastage. Nor do I see an adjustment for children versus adults. I’ve seen other calculations of and extra daily 150 calories (women) to 300 calories (men). Even the lower numbers could explain our explosion of overweight and obesity.

Steve Parker, M.D.

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May 16, 2012 · 2:00 AM

Random Thoughts On Paleo Eating for People With Diabetes

Not really pertinent, but I like buffalo

I was interviewed a couple months ago by Amy Stockwell Mercer, author of Smart Woman’s Guide to Diabetes. All I knew beforehand was that she was interested in my thoughts on the paleo diet as applied to diabetes.  I think she had run across my PaleoDiabetic blog.

In preparation, I collected some random thoughts and did a little research.

What’s the paleo diet?

Fresh, minimally processed food. Meat (lean or not? supermarket vs yuppiefied?), poultry, eggs, fish, leafy greens and other vegetables, nuts, berries, fruit, and probably tubers.

Non-paleo: highly processed, grains, refined sugars, industrial plant/seed oils, legumes, milk, cheese, yogurt.

The paleo diet is also called Old Stone Age, caveman, ancestral, hunter-gatherer, and Paleolithic diet.

Is the paleo diet deficient in any nutrients?

A quick scan of Loren Cordain’s website found mention of possible calcium and vitamin D deficits. Paleoistas will get vitamin D via sun exposure and fish (especially cold-water fatty fish). Obtain calcium from broccoli, kale, sardines, almonds, collards. (I wonder if the Recommended Dietary Allowance for calcium is set too high.)

What About Carbohydrates and Diabetes and the Paleo Diet?

Diabetes is a disorder of carbohydrate metabolism. In a way, it’s an intolerance of carbohydrates. In type 1 diabetes, there’s a total or near-total lack of insulin production on an autoimmune basis. In type 2 diabetes, the body’s insulin just isn’t working adequately; insulin production can be high, normal or low. In both cases, ingested carboydrates can’t be processed in a normal healthy way, so they stack up in the bloodstream as high blood sugars. If not addressed adequately, high blood glucose levels sooner or later will poison body tissues . Sooner in type 1, later in type 2. (Yes, this is a gross over-simplification.)

Gluten-rich Neolithic food

If you’re intolerant of lactose or gluten, you avoid those. If you’re intolerant of carbohydrates, you could avoid eating them, or take drugs to help you overcome your intolerance. Type 1 diabetics must take insulin. Insulin’s more optional for type 2’s. We have 11 classes of drugs to treat type 2 diabetes; we don’t know the potential adverse effects of most of these drugs. Already, three diabetes drugs have been taken off the U.S. market or severely restricted due to unacceptable toxicity: phenformin, troglitazone, and rosiglitazone.

Humans need two “essential fatty acids” and nine “essential” amino acids derived from proteins. “Essential” means we can’t be healthy and live long without them. Our bodies can’t synthesize them. On the other hand, there are no essential carbohydrates. Our bodies can make all the carbohydrate (mainly glucose) we need.

Since there are no essential carbohydrates, and we know little about the long-term adverse side effects of many of the diabetes drugs, I favor carbohydrate restriction for people with carboydrate intolerance. (To be clear, insulin is safe, indeed life-saving, for those with type 1 diabetes.)

That being said, let’s think about the Standard American Diet (SAD) eaten by an adult. It provides an average of 2673 calories a day. Added sugars provide 459 of those calories, or 17% o the total. Grains provide 625 calories, or 23% of the total. And most of those sugars and grains are in processed, commercial foods. So added sugars and grains provide 40% of the total calories in the SAD. (Figures are from an April 5, 2011, infographic at Civil Eats.)

Anyone going from the SAD to pure Paleo eating will be drastically reducing intake of added sugars and grains, our current major sources of carbohydrate. Question is, what will they replace those calories with?

That’s why I gave a thumbnail sketch of the paleo diet above. Take a gander and you’ll see lots of low-carb and no-carb options, along with some carb options. For folks with carbohydrate intolerance, I’d favor lower-carb veggies and judicious amounts of fruits, berries, and higher-carb veggies and

Will these cause bladder cancer? Pancreatitis?

tubers. “Judicious” depends on the individual, considering factors such as degree of residual insulin production, insulin sensitivity, the need to lose excess weight, and desire to avoid diabetes drugs.

Compared to the standard “diabetic diet” (what’s that?) and the Standard American Diet, switching to paleo should lower the glycemic index and glycemic load of the diet. Theoretically, that should help with blood sugar control.

A well-designed low-carb paleo diet would likely have at least twice as much fiber as the typical American diet, which would also tend to limit high blood sugar excursions.

In general, I favor a carbohydrate-restricted paleo diet for those with diabetes who have already decided to “go paleo.” I’m not endorsing any paleo diet for anyone with diabetes at this point—I’m still doing my research. But if you’re going to do it, I’d keep it lower-carb.  E.g., under 100 g of digestible carb daily. It has a lot of potential.

Are There Any Immediate Dangers for a Person With Diabetes Switching to the Paleo Diet?

It depends on three things: 1) current diet, and 2) current drug therapy, and 3) the particular version of paleo diet followed.

Remember, the Standard American Diet provides 40% of total calories as added sugars and grains (nearly all highly refined). Switching from SAD to a low-carb paleo diet will cut carb intake and glycemic load substantially, raising the risk of hypoglycemia if the person is taking certain drugs.

Drugs with potential to cause hypoglycemia include insulin, sulfonylureas, meglitinides, pramlintide, and perhaps thiazolidinediones.

Who knows about carb content of the standard “diabetic diet”? Contrary to poplular belief, there is no monolithic “diabetic diet.” There is no ADA diet (American Diabetes Association). My impression, however, is that the ADA favors relatively high carbohydrate consumption, perhaps 45-60% of total calories. Switching to low-carb paleo could definitely cause hypoglycemia in those taking the aforementioned drugs.

One way to avoid diet-induced hypoglycemia is to reduce the diabetic drug dose.

A type 2 overweight diabetic eating a Standard American Diet—and I know there are many out there—would tend to see lower glucose levels by switching to probably any of the popular paleo diets. Be ready for hypoglycemia if you take those drugs.

Paleo diets are not necessarily low-carb. Konner and Eaton estimate that ancestral hunter-gatherers obtained 35 to 40% of total calories from carbohydrates. I’ve seen other estimates as low as 22%. Reality likely falls between 22 and 65%. When pressed for a brief answer as to how many carbohydrate calories are in the paleo diet, I say “about a third of the total.” By comparison, the typical U.S. diet provides 50% of calories from carbohydrate.

Someone could end up with a high-carb paleo diet easily, by emphasizing tubers (e.g., potatoes), higher-carb vegetables, fruits, berries, and nuts (especially cashews). Compared with the SAD, this could cause higher or lower blood sugars, or no net change.

A diabetic on a Bernstein-style diet or Ketogenic Mediterranean Diet (both very-low-carb) but switching to paleo or low-carb paleo (50-150 g?) would see elevated blood sugars. Perhaps dangerously high glucoses.

Any person with diabetes making a change in diet should do it in consultation with a personal physician or other qualified healthcare professional familiar with their case.

Steve Parker, M.D.

Fun Facts!

  • A typical carbonated soda contain the equivalent of 10 tsp (50 ml) of sugar.
  • The typical U.S. adult eats 30 tsp (150 ml) daily of added sweeteners and sugars.
  • U.S total grain product consumption was at record lows in the 1970s, at 138 pounds per person. By 2000, grain consumption was up by 45%, to 200 pounds per person.
  • Total caloric sweetener consumption (by dry weight) was 110 pounds per person in the 1950s. By 2000, it was up 39% to 150 pounds.
  • Between 1970 and 2003, consumption of added fats and oils rose by 63%, from 53 to 85 pounds. [How tasty would that be without starches and sugars? Not very.]
  • In 2008, “added fat” calories in the U.S. adult diet were 641 (24% of total calories).

Fun Facts provided by the U.S. Department of Agriculture.

 

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March 29, 2012 · 2:00 AM

Evidence for Human Grain Consumption 100,000 Years Ago

ScienceDaily on December 17, 2009, reported findings of a Canadian archeological team who found evidence of systematic grain consumption by ancient humans in Africa:

The consumption of wild cereals among prehistoric hunters and gatherers appears to be far more ancient than previously thought, according to a University of Calgary archaeologist who has found the oldest example of extensive reliance on cereal and root staples in the diet of early Homo sapiens more than 100,000 years ago.

Neolithic technology

This is interesting to me because I’m investigating whether the paleo diet is a good one for people with diabetes.  In case you’re new to the paleo diet, grains are considered verboten by most adherents.  (The paleo diet is also known as the Stone Age diet, caveman diet, and Paleolithic diet.)  The cereal grain mentioned in the ScienceDaily article is wild sorghum.

Many in the paleosphere believe that such ancient humans didn’t have the technical skills to transform wild grains into something edible on a regular basis.  I haven’t read the source material, nor do I have an opinion on whether the archeologists are correct.  I’m just sayin’…

Steve Parker, M.D.

Reference: Mercader, Julio,  et al.  Mozambican grass seed consumption during the Middle Stone Age. Science, December 18, 2009.

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October 11, 2010 · 7:18 AM

Paleo Diet for Heart Patients With Diabetes and Prediabetes

A Paleolithic diet lowered blood sugar levels better than a control diet in coronary heart disease patients with elevated blood sugars, according to Swedish researchers reporting in 2007.

About half of patients with coronary heart disease have abnormal glucose (blood sugar) metabolism.  Lindeberg and associates wondered if a Paleolithic diet (aka “Old Stone Age,” “caveman,” or ancestral human diet) would lead to improved blood sugar levels in heart patients, compared to healthy, Mediterranean-style, Western diet.

Methodology

Investigators at the University of Lund found enrolled 38 male heart patients—average age 61—patients and randomized them to either a paleo diet or a “consensus” (Mediterranean-like) diet to be followed for 12 weeks.  Average weight was 94 kg.  Nine participants dropped out before completing the study, so results are based on 29 participants.  All subjects had either prediabetes or type 2 diabetes (the majority) but none were taking medications to lower blood sugar.  Baseline hemoglobin A1c’s were around 4.8%.  Average fasting blood sugar was 125 mg/dl (6.9 mmol/l); average sugar two hours after 75 g of oral glucose was 160 mg/dl (8.9 mmol/l).

The paleo diet was based on lean meat, fish, fruits, leafy and cruciferous vegetables, root vegetables (potatoes limited to two or fewer medium-sized per day), eggs, and nuts (no grains, rice, dairy products, salt, or refined fats and sugar). 

The Mediterranean-like diet focused on low-fat dairy, whole grains, vegetables, fruits, potatoes, fatty fish, oils and margarines rich in monounsaturated fatty acids and alpha-linolenic acid. 

Both groups were allowed up to one glass of wine daily.

No effort was made to restrict total caloric intake with a goal of weight loss.

Results

Absolute carbohydrate consumption was 43% lower in the paleo group (134 g versus 231 g), and 23% lower in terms of total calorie consumption (40% versus 52%).  Glycemic load was 47% lower in the paleo group (65 versus 122), mostly reflecting lack of cereal grains.

The paleo group ate significantly more nuts, fruit, and vegetables.  The Mediterranean group ate significantly more cereal grains,oil, margarine, and dairy products.

Glucose control improved by 26% in the paleo group compared to 7% in the consensus group.  The improvement was statisically significant only in the paleo group.  The researchers believe the improvement was independent of energy consumption, glycemic load, and dietary carb/protein/fat percentages.

High fruit consumption inthe paleo group (493 g versus 252 g daily) didn’t seem to impair glucose tolerance. 

Hemoglobin A1c’s did not change or differ significantly between the groups.

Neither group showed a change in insulin sensitivity (HOMA-IR method).

Comments

The authors’ bottom line:

In conclusion, we found marked improvement of glucose tolerance in ischemic heart disease patients with increased blood glucose or diabetes after advice to follow a Palaeolithic [sic] diet compared with a healthy Western diet.  The larger improvement of glucose tolerance in the Palaeolithic group was independent of energy intake and macronutrient composition, which suggests that avoiding Western foods is more important than counting calories, fat, carbohydrate or protein.  The study adds to the notion that healthy diets based on whole-grain cereals and low-fat dairy products are only the second best choice in the prevention and treatment of type 2 diabetes.

This was a small study; I consider it a promising pilot.  Results apply to men only, and perhaps only to Swedish men.  I have no reason to think they wouldn’t apply to women, too.  Who knows about other ethnic groups?

This study and the one I mention below are the only two studies I’ve seen that look at the paleo diet as applied to human diabetics.  If you know of others, please mention in the Comments section. 

The higher fruit consumption of the paleo group didn’t adversely affect glucose control, which is surprising.  Fruit is supposed to raise blood sugar.  At 493 grams a day, men in the paleo group ate almost seven times the average fruit intake of Swedish men (75 g/day).  Perhaps lack of adverse effect on glucose control here reflects that these diabetics and prediabetics were mild cases early in the course of the condition—diabetes tends to worsen over time.

ResearchBlogging.orgPresent day paleo and low-carb advocates share a degree of simpatico, mostly because of carbohydrate restriction—at least to some degree—by paleo dieters.  Both groups favor natural, relatively unprocessed foods.  Note that the average American eats 250-300 g of carbohydrates a day.  Total carb intake in the paleo group was 134 g (40% of calories) versus 231 g (55% of calories) in the Mediterranean-style diet.  Other versions of the paleo diet will yield different numbers, as will individual choices for various fruits and vegetables.  Forty percent of total energy consumption from carbs barely qualifies as low-carb. 

Study participants were mild, diet-controlled diabetics or prediabetics, not representative of the overall diabetic population, most of whom take drugs for it and have much higher hemoglobin A1c’s.

Lindeberg and associates in 2009 published results of a paleo diet versus standard diabetic diet trial in 13 diabetics.  Although a small trial (13 subjects, crossover design), it suggested advantages to the paleo diet in terms of heart disease risk factors and improved hemoglobin A1c.  Most participants were on glucose lowering drugs; none were on insulin.  Glucose levels were under fairly good control at the outset.  Compared to the standard diabetic diet, the Paleo diet yielded lower hemoglobin A1c’s (0.4% lower—absolute difference), lower trigylcerides, lower diastolic blood pressure, lower weight, lower body mass index, lower waist circumference, lower total energy (caloric) intake, and higher HDL cholesterol.  Glucose tolerance was the same for both diets.  Fasting blood sugars tended to decrease more on the Paleo diet, but did not reach statistical significance (p=0.08).

The paleo diet shows promise as a treatment or preventative for prediabetes and type 2 diabetes.  Only time will tell if it’s better than a low-carb Mediterranean diet or other low-carb diets. 

Steve Parker, M.D.

Reference: Lindeberg, S., Jönsson, T., Granfeldt, Y., Borgstrand, E., Soffman, J., Sjöström, K., & Ahrén, B. (2007). A Palaeolithic diet improves glucose tolerance more than a Mediterranean-like diet in individuals with ischaemic heart disease Diabetologia, 50 (9), 1795-1807 DOI: 10.1007/s00125-007-0716-y

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June 12, 2010 · 4:42 AM

Whole Grains in Diabetics: A Double-Edged Sword

 Whole grain and bran consumption are linked to reduced overall death rates and cardiovascular disease deaths in white women with type 2 diabetes, according to recent research from Boston-based investigators.

This is an important association since diabetics are prone to develop cardiovascular disease and suffer premature death.  Anything that can easily counteract those trends is welcome.

Several prior studies have found lower rates of cardiovascular disease in the general public eating whole grains.  I’m referring to fewer heart attacks and strokes, and fewer deaths from cardiovascular disease.

On the other hand, the carbohydrate content of whole grain products has the potential to complicate day-to-day management of diabetes by spiking blood sugars too high.  Too-high blood sugars aren’t healthy.  So, there’s the double edge.

What’s the Evidence That Whole Grains and Bran Prevent Death in Diabetics ?

ResearchBlogging.orgThe Harvard researchers followed 7,822 type 2 diabetic women in the massive Nurses’ Health Study over 26 years, during which 852 women died from any cause, including 295 from cardiovascular disease (195 from coronary heart disease, 100 from stroke).  Food-frequency questionnaires were administered periodically to the participants, with attention to whole grain and its components: cereal fiber, bran, and germ.  The hard clinical end-point in this study was death—from any and all causes, and from cardiovascular disease.   

Results

  • After adjustment for age and lifestyle and other dietary factors, only bran consumption was inversely associated with all-cause mortality: 25% lower risk of death for those eating an average of 10 g per day compared to 1 g per day.  In other words,the women who ate the most bran had the lowest risk of dying from any cause.
  • After adjustment for age and lifestyle and other dietary factors, whole grain intake trended towards protection against all-cause death, but not quite to the point of statistical significance.  Average highest consumption was 33 g per day, compared to lowest intake at 5 g per day. 
  • Bran consumption was consistently associated with lower risk of cardiovascular death: 35% lower risk comparing highest (10 g/day) with lowest consumption (1 g/day). 
  • “Added bran” was as protective against cardiovascular death as naturally occuring bran. 
  • Whole grain tended to protect against cardiovascular death, but did not reach statistical significance in the model adusting for lifestyle and other dietary variables (even when comparing 33 g/day to 5 g/day)
  • Whole grain and cereal fiber were inversely associated with all-cause and cardiovascular mortality when the investigators adjusted only for age, disregarding the possible effects of smoking, alcohol, overweight, physical activity, family history of heart disease, hormone therapy, duration of diabetes, total energy intake, fat intake (polyunsatrurated, trans-, saturated), magnesium, and folate.

The Researchers’ Conclusions

Whole-grain and bran intakes were associated with reduced all-cause and cardiovascular disease-specific mortality in women with diabetes mellitus. These findings suggest a potential benefit of whole-grain intake in reducing mortality and cardiovascular risk in diabetic patients.

The authors point out that whole grain and its components may be protective since they:

  • reduce blood lipids
  • lower blood pressure
  • reduce hyperinsulinemia and improve glucose control
  • improve performance of the arterial wall lining (endothelium)
  • reduce oxidative stress and iflammation

My Comments

Whole grain and bran consumption may indeed protect against death and cardiovascular disease in diabetic white women, but the effect is by no means dramatic.  I had speculated earlier whether whole grain intake might be particularly protective in diabetics, but this study suggests not.  Clearly, whole grains are no panacea. 

Diabetics hoping to avoid cardiovascular disease are well-advised to pay attention to—and modify—non-dietary risk factors for heart disease, such as obesity, smoking, and sedentary lifestyle.  Non-dietary issues probably outweigh the effects of diet, assuming blood sugars are reasonably controlled.

The traditional Mediterranean diet—prominently featuring whole grains—is associated with longer lifespan and less cardiovascular disease.   Canadian researchers in 2009 found moderately strong evidence that whole grains protect against coronary heart disease in the general population.  Yet a 2009 study did not find cereals contributing to the longer lifespan. 

I’m starting to think that the effect of diet on chronic disease is not as powerful as we have hoped.  

Steve Parker, M.D.

Reference: 
He, M., van Dam, R., Rimm, E., Hu, F., & Qi, L. (2010). Whole-Grain, Cereal Fiber, Bran, and Germ Intake and the Risks of All-Cause and Cardiovascular Disease-Specific Mortality Among Women With Type 2 Diabetes Mellitus Circulation, 121 (20), 2162-2168 DOI: 10.1161/CIRCULATIONAHA.109.907360

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April 24, 2010 · 8:21 AM

Whole Grains Reduce Heart Attacks and Strokes

Whole grain consumption is associated with a 21% reduction in cardiovascular disease when compared to minimal whole grain intake, according to a 2008 review article in Nutrition, Metabolism, and Cardiovascular Disease.   

Coronary heart disease is the No. 1 killer in the developed world.  Stroke is No. 3.  The term “cardiovascular disease” lumps together heart attacks, strokes, high blood pressure,  and generalized atherosclerosis (hardening of the arteries). 

Investigators at Wake Forest University reviewed seven pertinent studies looking at whole grains and cardiovascular disease.  The studies looked at groups of people, determining their baseline food consumption via questionnaire, and noted disease development over time.  These are called “prospective cohort studies.” 

None of these cohorts was composed purely of diabetics.

The people eating greater amounts of whole grain (average of 2.5 servings a day) had 21% lower risk of cardiovascular disease events compared to those who ate an average of 0.2 servings a day.  Disease events included heart disease, strokes, and fatal cardiovascular disease.  The lower risk was similar in degree whether the focus was on heart disease, stroke, or cardiovascular death.

Note that refined grain consumption was not associated with cardiovascular disease events. 

Why does this matter?

The traditional Mediterranean diet is rich in whole grains, which may help explain why the diet is associated with lower rates of cardiovascular disease.  If we look simply at longevity, however, a recent study found no benefit to the cereal grain component of the Mediterranean diet.  Go figure . . . doesn’t add up. 

Readers here know that over the last four months I’ve been reviewing the nutritional science literature that supports the disease-suppression claims for consumption of fruits, vegetables, and legumes.  I’ve been disappointed.  Fruit and vegetable consumption does not lower risk of cancer overall, nor does it prevent heart disease.  I haven’t found any strong evidence that legumes prevent or treat any disease, or have an effect on longevity.  Why all the literature review?  I’ve been deciding which healthy carbohydrates diabetics and prediabetics should add back into their diets after 8–12 weeks of the Ketogenic Mediterranean Diet.

The study at hand is fairly persuasive that whole grain consumption suppresses heart attacks and strokes and cardiovascular death.  [The paleo diet advocates and anti-gluten folks must be disappointed.]  I nominate whole grains as additional healthy carbs, perhaps the healthiest.

But . . .

. . .  for diabetics, there’s a fly in the ointment: the high carbohydrate content of grains often lead to high spikes in blood sugar.  It’s a pity, since diabetics are prone to develop cardiovascular disease and whole grains could counteract that.  We need a prospective cohort study of whole grain consumption in diabetics.  It’ll be done eventually, but I’m not holding my breath.

[Update June 12, 2010: The aforementioned study has been done in white women with type 2 diabetes.  Whole grain and bran consumption do seem to protect them against overall death and cardiovascular death.  The effect is not strong.]

What’s a guy or gal to do with this information now?

Non-diabetics:  Aim to incorporate two or three servings of whole grain daily into your diet if you want to lower your risk of heart disease and stroke. 

Diabetics:  Several options come to mind:

  1. Eat whatever you want and forget about it [not recommended].
  2. Does coronary heart disease runs in your family?  If so, try to incorporate one or two servings of whole grains daily, noting and addressing effects on your blood sugar one and two hours after consumption.  Eating whole grains alone will generally spike blood sugars higher than if you eat them with fats and protein.  Review acceptable blood sugar levels here.
  3. Regardless of family history, try to eat one or two servings of whole grains a day, noting and addressing effects on your blood sugar.  Then decide if it’s worth it.  Do you have to increase your diabetic drug dosages or add a new drug?  Are you tolerating the drugs?  Can you afford them?    
  4. Assess all your risk factors for developing heart disease: smoking, sedentary lifestyle, high blood pressure, age, high LDL cholesterol, family history, etc.  If you have multiple risk factors, see Option #3.  And modify the risk factors under your control.   
  5. Get your personal physician’s advice.    

Steve Parker, M.D.

Extra Credit:  The study authors suggest a number of reasons—and cite pertinent scientific references—how whole grains might reduce heart disease:

  • improved glucose homeostasis (protection against insulin resistance, less rise in blood sugar after ingestion [compared to refined grains], improved insulin sensitivity or beta-cell function)
  • advantageous blood lipid effects (soluble fiber from whole grains [especially oats] reduces LDL cholesterol, lower amounts of the small LDL particles thought to be particularly damaging to arteries, tendency to raise HDL cholesterol and trigylcerides [seen with insulin resistance in the metabolic syndrome])
  • improved function of the endothelial cells lining the arteries (improved vascular reactivity)

Disclaimer:  All matters regarding your health require supervision by a personal physician or other appropriate health professional familiar with your current health status.  Always consult your personal physician before making any dietary or exercise changes.

Reference: Mellen, P.B, Walsh, T.F., and Herrington, D.M.  Whole grain intake and cardiovascular disease: a meta-analysis.  Nutrition, Metabolism and Cardiovascular Disease, 18 (2008): 283-290.

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April 11, 2010 · 2:00 AM

Longevity Components of the Mediterranean Diet

According to Greek researchers, the components of the Mediterranean diet that contribute to longer lifespan are:

  • moderate alcohol consumption
  • low consumption of meat
  • high consumption of vegetables, fruits, nuts, olive oil, and legumes

The following didn’t seem to contribute much, if any:

  • cereals (the grain of a grass such as wheat, corn, oats)
  • dairy products
  • fish and seafood

Investigators at the University of Athens examined the Greek portion of the European Prospective Investigation into Cancer (EPIC) and Nutrition, which included 23,349 men and women free of diabetes, cancer, and coronary heart disease at the outset.  Food habits were documented by questionnaire. 

The focus of this particular study was death rates over an average follow-up of 8.5 years.  Adherence to the traditional Mediterranean diet ranged from minimal to high, as would be expected. 

As with numerous other studies of the Mediterranean diet, higher adherence to the Mediterranean diet was associated with lower chance of death. 

My Comments

The lack of benefit from fish is unexpected.  I have no explanation.  A preponderance of evidence elsewhere suggests fish consumption helps prolong life via lowered rates of heart disease.

Alcohol can be dangerous, of course.  Some people should not partake, ever.     

For people with diabetes who wish to avoid the carbohydrate load in cereals and dairy products, you don’t need to worry much about cutting those out of an otherwise Mediterranean-style diet.

Steve Parker, M.D. 

Reference:  Trichopoulou, Antonia, et al.  Anatomy of health effects of the Mediterranean diet: Greek EPIC prospective cohort study.  British Medical Journal, 338 (2009): b2337.  DOI: 10.1136/bmj.b2337.

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Filed under Alcohol, Dairy Products, Fish, Fruits, Grains, Health Benefits, legumes, Mediterranean Diet, nuts, olive oil, Vegetables

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March 22, 2010 · 2:00 AM

Vinegar to Treat Diabetes?

Vinegar reduces blood sugar elevations after meals containing complex carbohydrates, according to the Department of Nutrition at Arizona State University.

Meals containing carbohydrates (and to a lesser extent, proteins) raise blood sugar after meals in people with or without diabetes.  [I’ve written previously about the normal ranges of blood sugars.]  Previous studies established that a single vinegar dose around mealtime lowers postprandial (after meal) blood sugar levels by up to 50%.  Arizona investigators wanted to know the best dose and timing for reducing postprandial blood sugar elevations.

They ran multiple tests on about 40 adults who reported they were generally healthy except nine had type 2 diabetes (not taking insulin). 

Findings

Mealtime vinegar ingestion reduced postprandial (two hours after meal)  blood sugars by about 20% compared to placebo.  The test meal was white bagel (variable amounts), 20 g of butter, and 200 g of juice. 

The most effective dose of vinegar was 10 g (about two teaspoons or 10 ml) of 5% acetic acid vinegar (either Heinz apple cider vinegar or Star Fine Foods raspberry vinegar).  This equates to two tablespoons of vinaigrette dressing (two parts oil/1 part vinegar) as might be used on a salad.  The authors also say that “…two teaspoons of vinegar could be consumed palatably in hot tea with lemon at mealtime.”

Discussion

The study authors suggest that the blood-sugar-lowering effect of vinegar may be related to inhibition of digestive enzymes or to a slower rate of empyting by the stomach.  Remember that most of digestion and absorption of nutrients occurs in the small intestine; the stomach first has to empty food into the small intestine.  Vinegar seems to inhibit digestion of starch but not of simple (monosaccharide) sugars.

They also note another study that found vinegar slowed the rate of stomach emptying by almost 40% in type 1 diabetics with gastoparesis, potentially raising the risk of low blood sugar.

Take-Home Points

The development of cardiovascular disease, like heart attacks and strokes, seems to be tied especially to elevations of blood sugar after meals as compared to before-meal or fasting sugar levels.  This may be related to formation of free radicals  and inflammatory mediators.  So reduction of postprandial blood sugar elevations by vinegar may be particularly helpful in preventing heart disease.  It will be many years before we can prove this by a clinical study, if ever. 

Diabetics, especially type 2’s without gastroparesis, may better tolerate grains, fruits, and legumes—in terms of lower blood sugar spikes—if they eat them in a meal that includes two teaspoons of vinegar. 

Steve Parker, M.D.

Reference:  Johnston, Carol, et al.  Examination of the antiglycemic properties of vinegar in healthy adults.  Annals of Nutrition and Metabolism, 56 (2010): 74-79.

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