Category Archives: Fat in Diet

Major U.S. Diet Changes over the Last 100 Years

Medical student Kris Gunnars has an article at Business Insider, of all places, that shows graphically many of the major U.S. dietary changes of the last hundred years. In this case, transmogrification may be a better term than mere “changes.” Much of the Western world has evolved in similar fashion.

You need to read the article and ponder the graphs if you question why we have so much obesity, type 2 diabetes, heart disease, hypertension, and perhaps cancer. You’ll see dramatic increases in consumption of added sugars, industrial seed oils (esp. soybean), soda pop and fruit juice (added sugar!), total calories, and fast food. You’ll see how much we’ve increased dining away from home. Butter consumption is down drastically, but doesn’t seem to have done us much good, if any.

Sugar cane

Sugar cane

 

There’s fairly good evidence that coronary artery disease (CAD) the cause of most heart attacks) was very prominent between 1960 to 2000 or so, but it’s been tapering off in recent years and didn’t seem to be very common 100 years ago. Understand that you can have it for 20 years or more before you ever have symptoms (angina) or a heart attack from it. In fact, the disease probably starts in childhood. I’ve always wondered about the cause of the CAD prevalence trends, and wondered specifically how much of the long-term trend was related to trans-fat consumption. But I’ve never been able to find good data on trans-fat consumption. Kris came up with a chart of margarine consumption, which may be a good proxy for trans-fats. Another of his charts includes shortening, a rich source of trans-fats and probably also a good proxy. I remember growing up in the 1960s that we always had a 1/2 gallon tin can of Crisco hydrogenated fat in the cupboard. Shortening consumption increased dramatically from 1955 until dropping like a rock around 2000.

The timeline curves for trans-fat consumption (by proxy) and prevalence of coronary heart disease seem to match up fairly well, considering a 20 year lag. In the early 1990s, we started cutting back on trans-fats, and here we are now with lower mortality and morbidity from coronary artery disease. (CAD is very complex; lower rates of smoking surely explain some of the recent trend.)

Read the whole enchilada. Very impressive. Highly recommended.

Steve Parker, M.D.

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Filed under Causes of Diabetes, coronary heart disease, Fat in Diet, Heart Disease

Supplemental Omega-3 Fats’ Effect on Heart Disease, Stroke, Cancer, and Death: No Relationship In a General Population

Salmon is one the the cold-water fatty fish loaded with omega-3 fatty acids

Salmon is one the the cold-water fatty fish loaded with omega-3 fatty acids

I’ve been sitting on this research report a few years, waiting until I had time to dig into it. That time never came. The full report is free online (thanks, British Medical Journal!). I scanned the full paper to learn that nearly all the studies in this meta-analysis used fish oil supplements, not the cold-water fatty fish the I recommend my patients eat twice a week.

Here’s the abstract:

Objective: To review systematically the evidence for an effect of long chain and shorter chain omega 3 fatty acids on total mortality, cardiovascular events, and cancer.

Data sources: Electronic databases searched to February 2002; authors contacted and bibliographies of randomised controlled trials (RCTs) checked to locate studies.

Review methods Review of RCTs of omega 3 intake for 3 6 months in adults (with or without risk factors for cardiovascular disease) with data on a relevant outcome. Cohort studies that estimated omega 3 intake and related this to clinical outcome during at least 6 months were also included. Application of inclusion criteria, data extraction, and quality assessments were performed independently in duplicate.

Results: Of 15 159 titles and abstracts assessed, 48 RCTs (36 913 participants) and 41 cohort studies were analysed. The trial results were inconsistent. The pooled estimate showed no strong evidence of reduced risk of total mortality (relative risk 0.87, 95% confidence interval 0.73 to 1.03) or combined cardiovascular events (0.95, 0.82 to 1.12) in participants taking additional omega 3 fats. The few studies at low risk of bias were more consistent, but they showed no effect of omega 3 on total mortality (0.98, 0.70 to 1.36) or cardiovascular events (1.09, 0.87 to 1.37). When data from the subgroup of studies of long chain omega 3 fats were analysed separately, total mortality (0.86, 0.70 to 1.04; 138 events) and cardiovascular events (0.93, 0.79 to 1.11) were not clearly reduced. Neither RCTs nor cohort studies suggested increased risk of cancer with a higher intake of omega 3 (trials: 1.07, 0.88 to 1.30; cohort studies: 1.02, 0.87 to 1.19), but clinically important harm could not be excluded.

Conclusion: Long chain and shorter chain omega 3 fats do not have a clear effect on total mortality, combined cardiovascular events, or cancer.

Reference: Hooper, Lee et al. Risks and benefits of omega 3 fats for mortality, cardiovascular disease, and cancer: systematic review. BMJ  2006;332:752-760 (1 April), doi:10.1136/bmj.38755.366331.2F (published 24 March 2006).

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Filed under coronary heart disease, Diabetes Complications, Fat in Diet, Fish, Heart Disease, Longevity, Stroke

Low-Carb Diet Improves Glucose Control in Japanese Type 2 Diabetics

Mt. Fuji in Japan

Mt. Fuji in Japan

I don’ know anything about Japanese T2 diabetes. I’ve never studied it. Their underlying physiology may or may not be the same as in North American white diabetics, with whom I am much more familiar.

For what it’s worth, a small study recently found improvement of blood sugar control and triglycerides in those on a carbohydrate restricted diet versus a standard calorie-restricted diet.

Only 24 patients were involved. Half were assigned to eat low-carb without calorie restriction; the other half ate the control diet. The carbohydrate-restricted group aimed for 70-130 grams of carb daily, while eating more fat and protein than the control group. The calorie-restricted guys were taught how to get 50-60% of calories from carbohydrate and keep fat under 25% of calories. At the end of the six-month study, the low-carbers were averaging 125 g of carb daily, compare to 200 g for the other group. By six months, both groups were eating about the same amount of calories.

Average age was 63. Body mass index was 24.5 in the low-carb group and 27 in the controls. (If you did the research, I bet you’d find Japanese T2 diabetics have lower BMIs than American diabetics.) All were taking one or more diabetes drugs.

The calorie-restricted group didn’t change their hemoglobin A1c (a standard measure of glucose control) from 7.7%. The low-carb group dropped their hemoglobin A1c from 7.6 to 7.0% (statistically significant). The low-carb group also cut their triglycerides by 40%. Average weights didn’t change in either group.

Bottom Line

This small study suggests that mild to moderate carbohydrate restriction helps control diabetes in Japanese with type 2 diabetes. The improvement in hemoglobin A1c is equivalent to that seen with initiation of many diabetes drugs. I think further improvements in multiple measures would have been seen if carbohydrates had been restricted even further.

Steve Parker, M.D.

Link to reference.

h/t Dr Michael Eades

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Filed under Carbohydrate, Fat in Diet

Can You Manage Your Type 2 Diabetes Without Drugs?

David Mendosa says you can. I’m not quite that optimistic, but probably a majority can, if they have the knowledge, discipline, and willpower. Here are some snippets from David’s blog:

You can use drugs to bring your A1C level down to normal. That’s a good thing. But this strategy does have its costs, and those costs aren’t just money out of your pocket or your checkbook. The worst of those costs are the potential side effects of the drugs.

***

But some of us think we have a safer strategy of managing our diabetes without drugs. Back in 2007 I joined this group with the encouragement of a good friend of mine who is a Certified Diabetes Educator. Before that, I had 14 years of experience taking a wide range of diabetes drugs, including two different sulfonylureas (Diaßeta and Amyrl), Glucophage (metformin), and Byetta. For the past six years I haven’t taking any diabetes drugs, and yet I keep my diabetes in control with an A1C level usually about 5.4.

I had to make three big changes in my life when I went off the diabetes drugs, and they are hard at first. But now they are a routine part of my life, and I would never go back to my old ways. The changes that I had to make are those that almost everyone who has diabetes has to make. In order of importance, I had (1) to lose weight, (2) eat fewer carbohydrates, and (3) exercise more.

Read the whole enchilada. It’s brief.

Steve Parker, M.D.

 

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Filed under Exercise, Fat in Diet

Large Breakfast Rich in Protein and Fat Beats a Small Breakfast Strategy in Type 2 Diabetes

…according to research reported at MedPageToday.  This was a relatively small study with about 30 participants in each treatment arm. A snippet:

Patients in the big-breakfast group were instructed to consume 33% of their daily calories in their morning meal — that included up to 30% protein, up to 37% fat, and the rest in carbohydrates. Patients in the small-breakfast group were instructed to consume 12.5% of their daily calories at breakfast — with up to 70% in the form of carbohydrates.

Average fasting glucose decreased 14.51 mg/dL in the big breakfast group and decreased 4.91 mg/dL in the small breakfast group (P=0.011), she said at the annual meeting of the European Association for the Study of Diabetes.

The big breakfast group also saw a significant drop in systolic blood pressure (almost 10 mmHg), although probably not to the point it created a problem.

Read the whole enchilada.

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Filed under Fat in Diet, Protein

Periodic Tests, Treatments, and Goals for PWDs (Persons With Diabetes)

If you don't like your physician, find a new one

If you don’t like your physician, find a new one

So, you’ve got diabetes. You’re trying to deal with it or you wouldn’t be here. You’ve got a heck of a lot of medical information to master.

Unless you have a good diabetes specialist physician on your team, you may not be getting optimal care. Below are some guidelines you may find helpful. The goal is to prevent diabetes complications. Many primary care physicians will not be up-to-date on the guidelines. Don’t hesitate to discuss them with your doctor. Nobody cares as much about your health as you do.

Annual Tests

The American Diabetes Association (ADA) recommends the following items be done yearly (except as noted) in non-pregnant adults with diabetes. (Incidentally, I don’t necessarily agree with all ADA guidelines.) The complete ADA guidelines are available on the Internet.

  • Lipid profile (every two years if results are fine and stable)
  • Comprehensive foot exam
  • Screening test for distal symmetric polyneuropathy: pinprick, vibration, monofilament pressure sense
  • Serum creatinine and estimate of glomerular filtration rate (MDRD equation)
  • Test for albumin in the urine, such as measurement of albumin-to-creatinine ratio in a random spot urine specimen
  • Comprehensive eye exam by an ophthalmologist or optometrist (if exam is normal, every two or three years is acceptable)
  • Hemoglobin A1c at least twice a year, but every three months if therapy has changed or glucose control is not at goal
  • Flu shots

Other Vaccinations, Weight Loss, Diabetic Diet, Prediabetes, Alcohol, Exercise, Etc.

Additionally, the 2013 ADA guidelines recommend:

  • Pneumococcal vaccination. “A one time re-vaccination is recommended for individuals >64 years of age previously immunized when they were <65 years of age if the vaccine was administered >5 years ago.” Also repeat the vaccination after five years for patients with nephrotic syndrome, chronic kidney disease, other immunocompromised states (poor ability to fight infection), or transplantation.
  • Hepatitis B vaccination to unvaccinated adults who are 19 through 59 years of age.
  • Weight loss for all overweight diabetics. “For weight loss, either low-carbohydrate, low-fat calorie-restricted, or Mediterranean diets may be effective in the short-term (up to two years).” For those on low-carb diets, monitor lipids, kidney function, and protein consumption, and adjust diabetic drugs as needed. The optimal macronutrient composition of weight loss diets has not been established. (Macronutrients are carbohydrates, proteins, and fats.)
  • “The mix of carbohydrate, protein, and fat may be adjusted to meet the metabolic goals and individual preferences of the person with diabetes.” “It must be clearly recognized that regardless of the macronutrient mix, total caloric intake must be appropriate to weight management goal.”
  • “A variety of dietary meal patterns are likely effective in managing diabetes including Mediterranean-style, plant-based (vegan or vegetarian), low-fat and lower-carbohydrate eating patterns.”
  • “Monitoring carbohydrate, whether by carbohydrate counting, choices, or experience-based estimation, remains a key strategy in achieving glycemic control.”
  • Limit alcohol to one (women) or two (men) drinks a day.
  • Limit saturated fat to less than seven percent of calories.
  • During the initial diabetic exam, screen for peripheral arterial disease (poor circulation). Strongly consider calculation of the ankle-brachial index for those over 50 years of age; consider it for younger patients if they have risk factors for poor circulation.
  • Those at risk for diabetes, including prediabetics, should aim for moderate weight loss (about seven percent of body weight) if overweight. Either low-carbohydrate, low-fat calorie-restricted, or Mediterranean diets may be effective in the short-term (up to 2 years). Also important is exercise: at least 150 minutes per week of moderate-intensity aerobic activity. “Individuals at risk for type 2 diabetes should be encouraged to achieve the U.S. Department of Agriculture (USDA) recommendation for dietary fiber (14 g fiber/1,000 kcal) and foods containing whole grains (one-half of grain intake).” Limit intake of sugar-sweetened beverages.
  • “Adults with diabetes should be advised to perform at least 150 min/week of moderate-intensity aerobic physical activity (50–70% of maximum heart rate), spread over at least 3 days/week with no more than two consecutive days without exercise. In the absence of contraindications, adults with type 2 diabetes should be encouraged to perform resistance training at least twice per week.”
  • Screening for coronary artery disease before an exercise program is depends on the physician judgment on a case-by-case basis. Routine screening is not recommended.
Steve Parker MD, low-carb diet, diabetic diet

Olive, olive oil, and vinegar: classic Mediterranean foods

Obviously, some of my dietary recommendations conflict with ADA guidelines. The experts assembled by the ADA to compose guidelines were well-intentioned, intelligent, and hard-working. The guidelines are supported by 528 scientific journal references. I greatly appreciate the expert panel’s work. We’ve simply reached some different conclusions. By the same token, I’m sure the expert panel didn’t have unanimous agreement on all the final recommendations. I invite you to review the dietary guidelines yourself, discuss with your personal physician, then decide where you stand.

General Blood Glucose Treatment Goals

The ADA in 2013 suggests these therapeutic goals for non-pregnant adults:

  • Fasting blood glucoses: 70 to 130 mg/dl (3.9 to 7.2 mmol/l)
  • Peak glucoses one to two hours after start of meals: under 180 mg/dl (10 mmol/l)
  • Hemoglobin A1C: under 7%
  • Blood pressure: under 140/80 mmHg
  • LDL cholesterol: under 100 mg/dl (2.6 mmol/l). (In established cardiovascular disease: <70 mg/dl or 1.8 mmol/l may be a better goal.)
  • HDL cholesterol: over 40 mg/dl (1.0 mmol/l) for men and over 50 mg/dl (1.3 mmol/l) for women
  • Triglycerides: under 150 mg/dl (1.7 mmol/l)

The American Association of Clinical Endocrinologists (AACE) in 2011 proposed somewhat “tighter” blood sugar goals for non-pregnant adults:

  • Fasting blood glucoses: under 110 mg/dl (6.11 mmol/l)
  • Peak glucoses 2 hours after start of meals: under 140 mg/dl (7.78 mmol/l)
  • Hemoglobin A1C: 6.5% or less

The ADA reminds clinicians, and I’m sure the AACE guys agree, that diabetes control goals should be individualized, based on age and life expectancy of the patient, duration of diabetes, other diseases that are present, individual patient preferences, and whether the patient is able to easily recognize and deal with hypoglycemia. I agree completely.

Steve Parker, M.D.

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Filed under Diabetes Complications, Exercise, Fat in Diet, Fiber, Mediterranean Diet, Overweight and Obesity, Prediabetes, Prevention of T2 Diabetes

Low-Carb Research Update

“What about that recent study in American Journal of Clinical Nutrition…?”

As much as possible, I base my nutrition and medical recommendations on science-based research published in the medical literature.  Medical textbooks can be very helpful, but they aren’t as up-to-date as the medical journals.

In the early 2000s, a flurry of research reports demonstrated that very-low-carb eating (as in Dr. Atkins New Diet Revolution) was safe and effective for short-term weight management and control of diabetes.  I was still concerned back then about the long-term safety of the high fat content of Atkins.  But 80 hours of literature review in 2009 allowed me to embrace low-carbohydrate eating as a logical and viable option for many of my patients.  The evidence convinced me that the high fat content (saturated or otherwise) of many low-carb diets was little to worry about over the long run.

By the way, have you noticed some of the celebrities jumping on the low-carb weight-management bandwagon lately?  Sharon Osbourne, Drew Carey, and Alec Baldwin, to name a few.

My primary nutrition interests are low-carb eating, the Mediterranean diet, and the paleo diet.  I’m careful to stay up-to-date with the pertinent scientific research.  I’d like to share with you some of the pertinent research findings of the last few years.

Low-Carb Diets

  • Low-carb diets reduce weight, reduce blood pressure, lower triglyceride levels (a healthy move), and raise HDL cholesterol (another good trend).  These improvements should help reduce your risk of heart disease.  (In the journal Obesity Reviews, 2012.)
  • Dietary fat, including saturated fat, is not a cause of vascular disease such as heart attacks and atherosclerosis (hardening of the arteries).  (Multiple research reports.)
  • If you’re overweight and replace two sugary drinks a day with diet soda or water, you’ll lose about four pounds over the next six months.  (American Journal of Clinical Nutrition, 2012.)
  • United States residents obtain 40% of total calories from grains and added sugars.  Most developed countries are similar.  Dr. Stephan Guyenet notes that U.S. sugar consumption increased steadily “…from 6.3 pounds [2.9 kg] per person per year in 1822 to 107.7 pounds [50 kg] per person in 1999.  Wrap your brain around this: in 1822 we ate the amount of added sugar in one 12-ounce can of soda every five days, while today we eat that much sugar every seven hours.”
  • A very-low-carb diet improves the memory of those with age-related mild cognitive impairment. Mild cognitive impairment is a precursor to dementia.  (University of Cincinnati, 2012.)
  • High-carbohydrate and sugar-rich diets greatly raise the risk of mild cognitive impairment in the elderly. (Mayo Clinic study published in the Journal of Alzheimers’ Disease, 2012.)
  • Compared to obese low-fat dieters, low-carb dieters lose twice as much fat weight.  (University of Cincinnati, 2011.)
  • Diets low in sugar and refined starches are linked to lower risk of age-related macular degeneration in women.  Macular degeneration is a major cause of blindness.  (University of Wisconsin, 2011.)
  • A ketogenic (very-low-carb) Mediterranean diet cures metabolic syndrome (Journal of Medicinal Food, 2011.)
  • For type 2 diabetics, replacing a daily muffin (high-carb) with two ounces (60 g) of nuts (low-carb) improves blood sugar control and reduces LDL cholesterol (the “bad” cholesterol). (Diabetes Care, 2011.)
  • For those afflicted with fatty liver, a low-carb diet beats a low-fat diet for management. (American Journal of Clinical Nutrition, 2011.)
  • For weight loss, the American Diabetes Association has endorsed low-carb (under 130 g/day) and Mediterranean diets, for use up to two years. (Diabetes Care, 2011.)
  • High-carbohydrate eating doubles the risk of heart disease (coronary artery disease) in women.  (Archives of Internal Medicine, 2010.)
  • One criticism of low-carb diets is that they may be high in protein, which in turn may cause bone thinning (osteoporosis).  A 2010 study shows this is not a problem, at least in women.  Men were not studied.  (American Journal of Clinical Nutrition.)
  • High-carbohydrate eating increases the risk of developing type 2 diabetes (American Journal of Clinical Nutrition, 2010.)
  • Obesity in U.S. children tripled from 1980 to 2000, rising to 17% of all children.  A low-carb, high-protein diet is safe and effective for obese adolescents.  (American Journal of Clinical Nutrition, 2010.)

Mediterranean Diet

The traditional Mediterranean diet is well established as a healthy way of eating despite being relatively high in carbohydrate: 50 to 60% of total calories.  It’s known to prolong life span while reducing rates of heart disease, cancer, strokes, diabetes, and dementia.  The Mediterranean diet is rich in fresh fruits, vegetables, nuts and seeds, olive oil, whole grain bread, fish, and judicious amounts of wine, while incorporating relatively little meat.  It deserves your serious consideration.  I keep abreast of the latest scientific literature on this diet.

  • Olive oil is linked to longer life span and reduced heart disease.  (American Journal of Clinical Nutrition, 2012.)
  • Olive oil is associated with reduced stroke risk.  (Neurology, 2012).
  • The Mediterranean diet reduces risk of sudden cardiac death in women.  (Journal of the American Medical Association, 2011.)
  • The Mediterranean diet is linked to fewer strokes visible by MRI scanning.  (Annals of Neurology, 2011.)
  • It reduces the symptoms of asthma in children.  (Journal of the American Dietetic Association, 2011.)
  • Compared to low-fat eating, it reduces the incidence of type 2 diabetes by 50% in middle-aged and older folks.  (Diabetes Care, 2010.)
  •  A review of all available well-designed studies on the Mediterranean diet confirms that it reduces risk of death, decreases heart disease, and reduces rates of cancer, dementia, Parkinson’s disease, stroke, and mild cognitive impairment.  (American Journal of Clinical Nutrition, 2010.)
  • It reduces the risk of breast cancer.  (American Journal of Clinical Nutrition, 2010.)
  • The Mediterranean diet reduces Alzheimer’s disease.   (New York residents, Archives of Neurology, 2010).
  • It slows the rate of age-related mental decline.  (Chicago residents, American Journal of Clinical Nutrition, 2010.)
  • In patients already diagnosed with heart disease, the Mediterranean diet prevents future heart-related events and preserves heart function.  (American Journal of Clinical Nutrition, 2010.)

Clearly, low-carb and Mediterranean-style eating have much to recommend them.  Low-carb eating is particularly useful for weight loss and management, and control of diabetes, prediabetes, and metabolic syndrome.  Long-term health effects of low-carb eating are less well established.  That’s where the Mediterranean diet shines.  That’s why I ask many of my patients to combine both approaches: low-carb and Mediterranean.  Note that several components of the Mediterranean diet are inherently low-carb: olive oil, nuts and seeds, fish, some wines, and many fruits and vegetables.  These items easily fit into a low-carb lifestyle and may yield the long-term health benefits of the Mediterranean diet.  If you’re interested, I’ve posted on the Internet a Low-Carb Mediterranean Diet that will get you started.

Steve Parker, M.D.

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.

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Filed under Carbohydrate, Fat in Diet, Health Benefits, Heart Disease, ketogenic diet, Mediterranean Diet, nuts, olive oil, Stroke, Vegetables, Weight Loss