…according to a recent report in Nutrition, Metabolism & Cardiovascular Disease. LDL cholesterol is the type we think contributes to coronary artery disease and other forms of atherosclerosis.
Learn about glycemic index at NutritionData.
My Low-Carb Mediterranean and Ketogenic Mediterranean Diets are undoubtedly “low glycemic index.” The Advanced Mediterranean Diet would also be significantly lower GI than the standard American diet.
Comments Off on Low Glycemic Index Diets Reduce LDL and Total Cholesterol
Filed under Glycemic Index and Load, Heart Disease
This is an epic post from my old Advanced Mediterranean Diet blog, originally dated July 6, 2009. That was a watershed year for me because of the ideas in this article. If you or your doctor think low-carb eating is dangerous because it may be higher in saturated fat, this post should convince you otherwise.
I’ve been thinking a lot lately about saturated fats. Weird, huh?
No saturated fat in grapes
In over two decades of clinical practice, I’ve never run across a patient willing to do that calculation. Not many physicians could tell you the “seven percent rule.”
One of the two major themes of Gary Taubes’ book, Good Calories, Bad Calories, is that dietary saturated fats are not particularly harmful to our health, if at all. From what I’ve been taught, this is sacrilegious. “Saturated fats are a major cause of heart disease and strokes,” I’ve heard and read over and over. In brief, this is the Diet-Heart Hypothesis or the “lipid hypothesis”: Dietary saturated fat, total fat, and cholesterol are directly related to coronary heart disease and other forms of atherosclerosis (aka hardening of the arteries).
In his review of Taubes’ book, Dr. George Bray didn’t even address Taubes’ point about saturated fats, writing instead, “read and decide for yourself.”
That started me thinking either that the Diet-Heart Hypothesis is indefensible or that Dr. Bray is lazy. I don’t think he’s lazy. Dr. Bray is a Grand High Pooh-Bah in the fields of obesity and nutrition.
The American Heart Association in 1957 recommended that polyunsaturated fats replace saturated fats.
U.S. public health recommendations in 1977 were to reduce fat intake to 30% of total calories to lower the risk of coronary heart disease. Slowly, some fats were replaced mostly with carbohydrates, highly refined ones at that. This shift tends to raise triglycerides and lower HDL cholesterol levels, which may themselves contribute to atherosclerosis. Current recommendations are, essentially, to keep saturated fatty acids as low as possible.
One concern about substituting carbohydrates for fats is that blood sugar levels rise, leading to insulin release from the pancreas, in turn promoting growth of fat tissue and potentially leading to weight gain. Some believe that the public health recommendation to reduce total fat (which led to higher carbohydrate intake) is the reason for the dramatic rise in overweight and diabetes we’ve seen over the last 30 years.
Note that if intake of saturated fats is inadequate, our bodies can make the saturated fats it needs from carbohydrates. These are generally the same saturated fats that are present in dietary fats of animal origin. The only exceptions are the two essential fatty acids: alpha-linolenic acid and linoleic acid.
Why would saturated fats be harmful? Apparently because they raise blood levels of cholesterol (including LDL cholesterol – “bad cholesterol”), which is thought to be a cause of atherosclerosis, which increases the risk of coronary heart disease and stroke. I don’t recall seeing any mention of a direct toxic effect of saturated fats (or fatty acids) on arterial walls, where the rubber meets the road. (Saturated fats are broken down in the small intestine to glycerol and fatty acids.)
Dietary saturated fats also raise HDL cholesterol – “good cholesterol” – although not to the degree they raise LDL.
You needed a break
Often overlooked in discussion of dietary fat effects is the great variability of response to fats among individuals. Response can depend on genetics, sex, fitness level, overweight or not, types of carbohydrates eaten, amount of total dietary fat, etc. And not all saturated fats affect cholesterol levels.
Many of the journal articles listed as references below support the idea that the link between dietary saturated fats and coronary heart disease is not strong, and may be nonexistent. Read them and you’ll find that:
“Read and decide for yourself,” indeed. I think you’ll begin to question the reigning dogma.
For example, here’s a conclusion from the Hooper article (from 2001):
In this review we have tried to separate out whether changes in individual fatty acid fractions are responsible for any benefits to health (using the technique of meta-regression). The answers are not definitive, the data being too sparse to be convincing. We are left with a suggestion that less total fat or less of any individual fatty acid fraction in the diet is beneficial.
And a conclusion of the J.B. German article:
At this time [2004], research on how specific saturated fatty acids contribute to coronary artery disease and on the role each specific saturated fatty acid play in other health outcomes is not sufficient to make global recommendations for all persons to remove saturated fats from their diet. No randomized clinical trials of low-fat diets or low-saturated fat diets of sufficient duration have been carried out; thus, there is a lack of knowledge of how low saturated fat intake can be without the risk of potentially deleterious health outcomes.
Zarraga and Schwartz (2006) conclude:
Numerous studies have been conducted to help provide dietary recommendations for optimal cardiovascular health. The most compelling data appear to come from trials that tested diets rich in fruits, vegetables, MUFAs [monounsaturated fatty acids], and PUFAs [polyunsaturated fatty acids], particularly the n-3 PUFAs. In addition, some degree of balance among various food groups appears to be a more sustainable behavioral practice than extreme restriction of a particular food group.
Here’s another of my favorite quotes on this topic, from the J.B. German article:
If saturated fatty acids were of no value or were harmful to humans, evolution would probably not have established within the mammary gland the means to produce saturated fatty acids . . . that provide a source of nourishment to ensure the growth , development, and survival of mammalian offspring.
Take-Home Points
The connection between dietary saturated fat and coronary heart disease is weak.
I may be excommunicated from the medical community for uttering this. You won’t hear it from most physicians or dietitians. They don’t have time to spend 80 hours on this topic, so they stick with the party line. And maybe I’m wrong anyway.
The scientific community is slowly moving away from the original Diet-Heart/Lipid Hypothesis. It is being replaced with stronger anti-atherosclerosis theories that promote:
So, saturated fats and dietary cholesterol are being crowded out of the picture, or ignored. In many cases, saturated fats have literally been replaced by poly- and monounsaturated fats (plant oils). Several clinical studies indicate that’s a healthy change, but it may be related more to the healthfulness of the plant oils than to detrimental effects of saturated fats.
The original Diet-Heart Hypothesis won’t die until the American Heart Association and U.S. public health agencies put a gun to its head and pull the trigger. That will take another 10 years or more.
If you want to hedge your bets, go ahead and limit your saturated fat intake. It probably won’t hurt you. It might help a wee bit. By the same token, I’m not going on an all-meat and cheese, ultra-high-saturated fat diet; I don’t want to miss out on the healthy effects of fruits, vegetables, whole grains, fish, nuts, and low-glycemic index carbohydrates. Some would throw red wine into the mix. This “prudent diet” reflects what I hereby christen The 21st Century Diet-Heart Hypothesis.
If you’re worried about coronary heart disease and atherosclerosis, spend less time counting saturated fat grams, and more time on other risk-reducing factors: diet modification as above, get regular exercise, control your blood pressure, achieve a healthy weight, and don’t smoke. More bang for the buck.
What do you think?
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.
Selected References Contradicting or Questioning the Diet-Heart Hypothesis (updated February 19, 2012):
Astrup, A., et al (including Ronald Krause, Frank Hu, and Walter Willett). The role of reducing intakes of saturated fat in the prevention of cardiovascular disease: where does the evidence stand in 2010. American Journal of Clinical Nutrition, 93 (2011): 684-688. (The authors believe that replacing saturated fats with polyunsaturated fats (but not carbohydrates) can reduce the risk of coronary heart disease (CHD). For the last four decades, low-fat diets replaced fat with carbohydates. So they believe saturated fatty acids cause CHD or polyunsaturated fatty acids prevent it. I see no mention of total fat intake in this article written by major names in nutritional epidemiology and lipid metabolism. “In countries following a Western diet, replacing 1% of energy intake from saturated fatty acids with polyunsaturated fatty acids has been associated with a 2–3% reduction in the incidence of CHD.” “Furthermore, the effect of particular foods on CHD cannot be predicted solely by their content of total saturated fatty acids because individual saturated fatty acids may have different cardiovascular effects and major saturated fatty acid food sources contain other constituents that could influence coronary heart disease risk.”) A Feb. 19, 2012, press release from the Harvard School of Public Health covered much of the same ground. It’s titled “Time to Stop Talking About Low-Fat, say HSPH Nutrition Experts.”
Siri-Tarino, Patty, et al. Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. American Journal of Clinical Nutrition, January 13, 2010. doi:10.3945/ajcn.2009.27725
Skeaff, C. Murray and Miller, Jody. Dietary fat and coronary heart disease: Summary of evidence from prospective cohort and randomised controlled trials. Annals of Nutrition and Metabolism, 55 (2009): 173-201.
Halton, Thomas, et al. Low-carbohydrate-diet score and the risk of coronary heart disease in women. New England Journal of Medicine, 355 (2006): 1,991-2,002.
German, J. Bruce, and Dillard, Cora J. Saturated fats: What dietary intake? American Journal of Clinical Nutrition, 80 (2004): 550-559.
Ravnskov, U. The questionable role of saturated and polyunsaturated fatty acids in cardiovascular disease. Journal of Clinical Epidemiology, 51 (1998): 443-460.
Ravsnskov, U. Hypothesis out-of-date. The diet-heart idea. Journal of Clinical Epidemiology, 55 (2002): 1,057-1,063.
Ravnskov, U, et al. Studies of dietary fat and heart disease. Science, 295 (2002): 1,464-1,465.
Taubes, G. The soft science of dietary fat. Science, 291 (2001): 2535-2541.
Zarraga, Ignatius, and Schwartz, Ernst. Impact of dietary patterns and interventions on cardiovascular health. Circulation, 114 (2006): 961-973.
Mente, Andrew, et al. A Systematic Review of the Evidence Supporting a Causal Link Between Dietary Factors and Coronary Heart Disease. Archives of Internal Medicine, 169 (2009): 659-669.
Parikh, Parin, et al. Diets and cardiovascular disease: an evidence-based assessment. Journal of the American College of Cardiology, 45 (2005): 1,379-1,387.
Bray, G.A. Review of Good Calories, Bad Calories. Obesity Reviews, 9 (2008): 251-263. Reproduced at the Protein Power website of Drs. Michael and Mary Dan Eades.
Hooper, L., et al. Dietary fat intake and prevention of cardiovascular disease: systematic review. British Medical Journal, 322 (2001): 757-763.
Weinberg, W.C. The Diet-Heart Hypothesis: a critique. Journal of the American College of Cardiology, 43 (2004): 731-733.
Mozaffarian, Darius, et al. Dietary fats, carbohydrate, and progression of coronary atherosclerosis in postmenopausal women. American Journal of Clinical Nutrition, 80 (2004): 1,175-1,184.
Related editorial: Knopp, Robert and Retzlaff, Barbara. Saturated fat prevents coronary artery disease? An American paradox. American Journal of Clinical Nutrition, 80 (2004): 1.102-1.103.
Yusuf, S., et al. Effect of potentially modifiable risk factors associated with myocardial infarction in 52 countries (the INTERHEART study): case-control study. Lancet, 364 (2004): 937-952. (ApoB/ApoA1 ratio was a risk factor for heart attack, so dietary saturated fat may play a role if it affects this ratio.)
Hu, Frank. Diet and cardiovascular disease prevention: The need for a paradigm shift. Journal of the American College of Cardiology, 50 (2007): 22-24. (Dr. Hu de-emphasizes the original diet-heart hypothesis, noting instead that “. . . reducing dietary GL [glycemic load] should be made a top public health priority.:)
Oh, K., et al. Dietary fat intake and risk of coronary heart disease in women: 20 years of follow-up of the Nurses’ Health Study. American Journal of Epidemiology, 161 (2005): 672-679.
Parker, Steve. Time to abandon the diet-heart hypothesis? Advanced Mediterranean Diet Blog, May 1, 2009.
Parker, Steve. New study confirms the heart-healthy Mediterranean diet. Advanced Mediterranean Diet Blog, April 14, 2009. (Examination of the Mente study listed above.)
Selected References Supporting the Diet-Heart Hypothesis (by no means exhaustive)
Ascherio, A. Epidemiologic studies on dietary fats and coronary heart disease. American Journal of Medicine, 113 (supplement) (2002): 9S-12S.
Griel, Amy and Kris-Etherton, Penny. Beyond saturated fat: The importance of the dietary fatty acid profile on cardiovascular disease. Nutrition Reviews, 64 (2006): 257-262. (Primarily a response to the Mozaffarian article above.)
Erkkila, Arja, et al. Dietary fatty acids and cardiovascular disease: An epidemiological approach. Progress in Lipid Research, 47 (2008): 172-187.
Filed under Fat in Diet, Heart Disease
Dieters on low-fat and low-carb diets both lost the same amount of weight after two years, according to a just-published article in Annals of Internal Medicine. Both groups received intensive behavioral treatment, which may be the key to success for many. Low-carb eating was clearly superior in terms of increased HDL cholesterol, which may help prevent heart disease and stroke.
The study was funded by the National Institutes of Health and was carried out in Denver, St. Louis, and Philadelphia.
How Was It Done?
Healthy adults aged 18-65 were randomly assigned to either a low-fat or low-carbohydrate diet. Average age was 45. Average body mass index was 36 (over 25 is overweight; over 30 is obese). Of the 307 participants, two thirds were women. People over 136 kg (299 lb) were excluded from the study—I guess because weight-loss through dieting is rarely successful at higher weights. Diabetics were excluded.
The low-carb diet: Essentially the Atkins diet with a prolonged induction phase (12 weeks instead of two). Started with maximum of 20 g carbs daily, as low-carb vegetables. Increase carbs by 5 g per week thereafter as long as weight loss progressed as planned. Fat and protein consumption were unlimited. The primary behavioral goal was to limit carb consumption.
The low-fat diet: Calories were limited to 1200-1500 /day (women) or 1500-1800 (men). [Those levels in general are too low, in my opinion.] Diet was to consist of about 55% of calories from carbs, 30% from fat, 15% from protein. The primary behavioral goal was to limit overall energy (calorie) intake.
Both groups received frequent, intensive in-person group therapy—lead by dietitians and psychologists—periodically over two years, covering such topics as self-monitoring, weight-loss tips, management of weight regain and noncompliance with assigned diet. Regular walking was recommended.
Body composition was measured periodically with dual X-ray absorptiometry.
What Did They Find?
Both groups lost about 11% of initial body weight, but tended to regain so that after two years, both groups average losses were only 7% of initial weight. Weight loss looked a little better at three months in the low-carb group, but it wasn’t statistically significant.
The groups had no differences in bone density or body composition.
No serious cardiovascular illnesses were reported by participants. During the first six months, the low-carb group reported more bad breath, hair loss, dry mouth, and constipation. After six months, constipation in the low-carb group was the only symptom difference between the groups.
During the first six months, the low-fat group had greater decreases in LDL cholesterol (with potentially less risk of heart disease), but the difference did not persist for one or two years.
Increases in HDL cholesterol (potentially heart-healthy) persisted throughout the study for the low-carb group. The increase was 20% above baseline.
About a third of participants in both groups dropped out of the study before the two years were up. [Not unusual.]
My Comments
Contrary to several previous studies that suggested low-carb diets are more successful than low-fat, the study at hand indicates they are equivalent as long as dieters get intensive long-term group behavioral intervention.
Low-carb critics warn that the diet will cause osteoporosis, a dangerous thinning of the bones that predisposes to fractures. This study disproves that.
Contrary to widespread criticism that low-carb eating—with lots of fat and cholestrol— is bad for your heart, this study notes a sustained elevation in HDL cholesterol (“good cholesterol”) on the low-carb diet over two years. This also suggests the low-carbers followed the diet fairly well. The investigators also note that low-carb eating tends to produce light, fluffy LDL cholesterol, which is felt to be less injurious to arteries compared to small, dense LDL cholesterol.
A major strength of the study is that it lasted two years, which is rare for weight-loss diet research.
A major weakness is that the investigators apparently didn’t do anything to document the participants’ degree of compliance with the assigned diet. It’s well known that many people in this setting can follow a diet pretty well for two to four months. After that, adherence typically drops off as people go back to their old habits. The group therapy sessions probably improved compliance, but we don’t know since it wasn’t documented.
How often do we hear “Diets don’t work.” Well, that’s just wrong.
Overall, it’s an impressive study, and done well.
Individuals wishing to lose weight on their own can’t replicate these study conditions because of the in-person behavioral intervention component. There are lots of self-help calorie-restricted balanced diets (e.g., Sonoma Diet, The Zone, Advanced Mediterranean Diet) and low-carb diets (e.g., Atkins Diet, Banting’s Letter on Corpulence, Low-Carb Mediterranean or Ketogenic Mediterranean Diets). On-line support groups—e.g. Low Carb Friends and SparkPeople and 3 Fat Chicks on a Diet—could supply some necessary behavioral intervention strategies and support.
Choosing a weight-loss program is not as easy as many think. [Well, I’ll admit that choosing the wrong one is easy.] I review the pertinent issues in my “Prepare for Weight Loss” page.
Reference: Foster, Gary, et al. Weight and metabolic outcomes after 2 years on a low-carbohydrate versus low-fat diet: a randomized trial. Annals of Internal Medicine, 153 (2010): 147-157 PMID: 20679559
Filed under Carbohydrate, Fat in Diet, ketogenic diet, Overweight and Obesity, Weight Loss
In overweight type 2 diabetics, a low-carbohydrate Mediterranean diet improved HDL cholesterol levels and glucose control better than either the standard Mediterranean diet or American Diabetes Association diet, according to Israeli researchers reporting earlier this year.
Background
Prior studies suggest that diets rich in monounsaturated fatty acids (olive oil, for example) elevate HDL cholesterol and reduce LDL cholestrol and triglycerides in type 2 diabetics.
Low-carb diets improve blood sugar levels and reduce excess body weight in type 2 diabetics, leading to the ADA’s allowance in 2008 of a low-carbohydrate diet as an alternative to standard diabetic diets.
Many—probably most—type 2 diabetics have insulin resistance: the body’s cells that can remove sugar from the bloodstream are not very sensitive to the effect of insulin driving sugar into those cells. They “resist” insulin’s effect. Consumption of monounsaturated fatty acids improves insulin sensitivity. In other words, insulin is better able to push blood sugar into cells, removing it from the bloodstream.
Previous studies have shown that both low-carb diets and the Mediterranean diet reduce after-meal elevations in blood sugar, which likely lowers levels of triglycerides and LDL cholesterol.
How Was the Study Done?
The goal was to compare effects of three diets in overweight type 2 diabetics in Israel over the course of one year. Study participants totalled 259. Average age was 56, average weight 86 kg (189 lb), average hemoglobin A1c 8.3%, and average fasting plasma glucose (sugar) was 10.3 mmol/L (185 mg/dl). [Many diabetics in the U.S. fit this profile.] People taking insulin were excluded from the study, as were those with proliferative diabetic retinopathy—no reasons given.
Participants were randomly assigned to one of three diets, so there were about 85 in each group. [Over the course of one year, people dropped out of the study for various reasons, leaving each group with about 60 subjects.]
Here are the diets:
Patients were followed-up by the same dietitian every two weeks for one year. All were advised to do aerobic exercise for 30-45 minutes at least three days a week.
Olive oil is traditionally the predominant form of fat in the Mediterranean diet and is a particularly rich source of monounsaturated fat. At no point in this report was olive oil mentioned, nor any other source of monounsaturated fat. Until I hear otherwise, I will assume that olive oil was the major source of monounsaturated fat in the TM and LCM diets.
All diets were designed to provide 20 calories per kilogram of body weight.
In all three diets, saturated fat provided 7% of total calories. Monounsaturated fatty acids provided 23% of total calories in the LCM, and 10% in the other two diets. Polyunsaturated fatty acids provided 15% of calories in the LCM, and 12% in the other two diets. The ADA diet provided 15 grams of fiber, the TM had 30 g, and the LCM had 45 g.
Adherence to the assigned diet was assessed with a “food frequency questionnaire” administered at six months.
What Did the Researchers Find?
Average reported energy intake was similar in all three groups: 2,222 calories per day.
Monounsaturated fat intake differences were statistically significant: 14.6, 12.8, and 12.6% for the LCM, TM, and ADA diets, respectively. Polyunsaturated fat intake differences were statistically significant: 12.9, 11.5, and 11.2% for the LCM, TM, and ADA diets, respectively.
Percentage of energy from carbs was highest for the ADA diet (45.4%), intermediate for the TM diet (45.2%), and lowest for the LCM diet (41.9%).
At the end of 12 months, all three groups lost about the same amount of weight (8-9 kg or 18-20 lb), body mass index, and waist circumference.
Hemoglobin A1c fell in all three groups, but was significantly greater for the LCM group than for the ADA diet (6.3% absolute value vs 6.7%).
Triglycerides fell in all three groups, but was significantly greater for the LCM diet compared to the ADA diet.
The LCM group achieved a significant increase (12%) in HDL cholesterol compared to the ADA diet, but not different from the TM group.
LDL cholesterol fell in all three groups, and the LCM group’s drop (25%) was clearly superior to that of the ADA diet (14%) but about the same as the TM diet (21%).
Conclusions of the Investigators
We found that an intensive community-based dietary intervention reduced cardiovascular risk factors in overweight patients with [type 2 diabetes] for all three diets. The LCM group had improved cardiovascular risk factors compared to either the ADA or the TM groups.
Only the LCM improved HDL levels and was superior to both the ADA and TM in improving glycaemic control.
It would appear that the low carbohydrate Mediterranean diet should be recommended for overweight diabetic patients.
My Comments
There’s no way the average diabetic could replicate this low-carb Mediterranean diet without working closely with a dietitian or nutritionist.
Any superiority of this low-carb Mediterranean diet may have as much to do with the increased monounsaturated fat intake as with the reduced carb consumption. Monounsaturated fatty acid consumption is thought to improve insulin sensitivity.
NutritionData’s Nutrient Search Tool can give you a list of foods high in monounsaturated fat.
The Mediterranean diet and low-carb diets independently have been shown to lower after-meal glucose levels, which probably lowers LDL cholesterol and triglycerides.
I’m disappointed the dietitians were not able to achieve a lower level of carbohydrate consumption in the low-carb Mediterranean diet group. I suspect if they had, improvements in glucose control and lipids would have been even better. But proof awaits another day.
We saw last year an article in the Annals of Internal Medicine that showed a dramatic reduction in the need for glucose-lowering drugs in type 2 diabetics following a different low-carb Mediterranean diet over four years, compared to a low-fat American Heart Association diet. These two studies convince me a low-carb Mediterranean diet has real life-preserving and life-enhancing potential.
Diabetics looking for a low-carb Mediterranean diet today have several options:
If you’re aware of any other low-carb, explicitly Mediterranean-style diets, please share in the Comments section.
References:
Elhayany, A., Lustman, A., Abel, R., Attal-Singer, J., and Vinker, S. A low carbohydrate Mediterranean diet improves cardiovascular risk factors and diabetes control among overweight patients with type 2 dabetes mellitus: a 1-year prospective randomized intervention study. Diabetes, Obesity and Metabolism, 12 (2010): 204-209.
Esposito, Katherine, et al. Effects of a Mediterranean-style diet on the need for antihyperglycemic drug therapy in patients with newly diagnosed type 2 diabetes. Annals of Internal Medicine, 151 (2009): 306-314.
Plant-based diets may offer special benefits to people with diabetes, according to a recent review article by U.S. researchers who reviewed the pertinent English language literature published since 1966. They found 116 potentially relevant articles, 10 of which were directly related to diabetes management and glucose control.
The authors failed to define “vegetarian” early on. Some vegetarians eat eggs, some eat cheese, some drink milk. I assume vegans eat no animal products whatsoever. On the last page of the review the authors write that a vegetarian “does not eat meat, fish, or poultry” although it’s not clear if that applies throughout the review. There are many references to “low-fat vegetarian” diets, with little or no mention of moderate- or high-fat vegetarian diets.
The authors often refer to vegetarian diets as “plant-based.” No doubt, they are. But even the healthy Mediterranean diet is considered plant-based, while clearly not vegetarian.
It’s also unclear whether they focused on type 1 or type 2 diabetes. My sense is, probably type 2.
Here are the major points:
My Comments
Have you heard of the Physicians Committee for Responsible Medicine? Their president is Neal Barnard, the lead author of the study at hand. He has a new book on reversal of diabetes with a low-fat vegetarian diet.
The authors cite a journal article (reference #16) in support of plant-based diets, but the article doesn’t mention a vegetarian or vegan diet—it’s high-carb, high-fiber diet. I didn’t review all 92 of their references to see if any others were misleading.
“Plant-based diets” must be a euphemism for vegetarian diets. Too many people shut down when you talk to them about vegetarian diets.
I won’t rule out the possibility that vegetarian/vegan diets may be helpful in management of diabetes. Such diets are, of course, 180 degrees different from the very low-carb diets I’ve reviewed favorably in these pages! Both models, ideally, move away from the over-processed, concentrated carbohydrates so prevalent in Western culture. Perhaps that’s the unifying healthy theme, if there is one.
Or different sub-types of diabetes respond better to particular diets.
I heartily agree with the authors that larger clinical trials of vegetarian diets in diabetics are needed. I’d love to see a long-term randomized controlled trial comparing a very low-carb diet diet with a low-fat vegetarian diet. That’s the best way to settle which is better for diabetics: vegetarian or low-carb.
It’ll never be done.
Has a vegetarian diet helped control your diabetes?
Reference: Barnard, Neal, et al. Vegetarian and vegan diets in type 2 diabetes management. Nutrition Reviews, 67(2009): 255-263. doi: 10.1111/j.1753-4887.2009.00198.x
Over three grams of fiber
High dietary fiber intake helps prevent constipation, diverticular disease, hemorrhoids, irritable bowel syndrome, and perhaps colon polyps. Soluble fiber helps control blood sugar levels in people with diabetes, and it reduces LDL cholesterol levels, thereby reducing risks of coronary heart disease.
An article in the journal Nutrition suggests how fiber may have beneficial effects in atherosclerosis (the cause of heart attacks and strokes), type 2 diabetes, and some cancers. These conditions are felt to be related to underlying systemic inflammation.
Systemic inflammation can be judged by blood levels of inflammatory markers such as interleukin-6, tumor necrosis factor-alpha-receptor-2, and high-sensitivity C-reactive protein.
Researchers looked at 1,958 postmenopausal women in the Women’s Health Initiative Observational Study, comparing inflammatory marker levels with dietary fiber intake. They found that high fiber intake was associated with significantly lower levels of inflammatory markers interleukin-6 and tumor necrosis factor-alpha-receptor-2. This association was true individually for total fiber, insoluble fiber, and soluble fiber. The researchers found no association with C reactive protein.
Bottom line? High intake of dietary fiber seems to reduce chronic inflammation, which may, in part, explain the observed clinical benefits of fiber.
Rest assured that the Mediterranean diet is naturally high in fiber.
High dietary fiber intake helps prevent constipation, diverticular disease, hemorrhoids, irritable bowel syndrome, and perhaps colon polyps.
Soluble fiber helps control blood sugar levels in people with diabetes, and it reduces LDL cholesterol levels, thereby reducing risks of coronary heart disease.
An article in the journal Nutrition suggests how fiber may have beneficial effects in atherosclerosis (the cause of heart attacks and strokes), type 2 diabetes, and some cancers. These conditions are felt to be related to underlying systemic inflammation.
Systemic inflammation can be judged by blood levels of inflammatory markers such as interleukin-6, tumor necrosis factor-alpha-receptor-2, and high-sensitivity C-reactive protein.
Researchers looked at 1,958 postmenopausal women in the Women’s Health Initiative Observational Study, comparing inflammatory marker levels with dietary fiber intake. They found that high fiber intake was associated with significantly lower levels of inflammatory markers interleukin-6 and tumor necrosis factor-alpha-receptor-2. This association was true individually for total fiber, insoluble fiber, and soluble fiber. The researchers found no association with C reactive protein.
Bottom line?
High intake of dietary fiber seems to reduce chronic inflammation, which may, in part, explain the observed clinical benefits of fiber.
Average adult fiber intake in the U.S. is 12 to 15 grams daily. Expert nutrition panels and the American Heart Association recommend 25 to 30 grams daily from whole grains, fruits, and vegetables.
Nutritionist Monica Reinagel at NutritionData.com has reviewed soluble vs insoluble fiber and good sources of soluble fiber: oranges, apples, carrots, oats and oat bran, psyllium husk, nuts, legumes, and flaxseed. Click the link for good sources of insoluble fiber.
Rest assured that the Mediterranean diet is naturally high in fiber.
Reference: Ma, Yensheng, et al. Association between dietary fiber and markers of systemic inflammation in the Women’s Health Initiative Observational Study. Nutrition, 24 (2008): 941-949.
Filed under Fiber
Click the pic to purchase at Amazon.com. E-book versions also available at Smashwords.com.
Bible Verse of the Day
Diabetic Mediterranean Diet 