Advanced Mediterranean Diet

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 was45.  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. 

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, Thin For Life,  Advanced Mediterranean Diet) and low-carb diets (e.g., the Atkins Diet,  the 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.

Steve Parker, M.D.

Reference: Foster GD, Wyatt HR, Hill JO, Makris AP, Rosenbaum DL, Brill C, Stein RI, Mohammed BS, Miller B, Rader DJ, Zemel B, Wadden TA, Tenhave T, Newcomb CW, & Klein S (2010). Weight and metabolic outcomes after 2 years on a low-carbohydrate versus low-fat diet: a randomized trial. Annals of internal medicine, 153 (3), 147-57 PMID: 20679559

Compared to the low-fat American Heart Association diet, the traditional Mediterranean diet rich in olive oil has more capacity to counteract potentially harmful “free radicals” and “reactive oxygen species” in our bodies, according to researchers at the University of Navarra in Spain.

Our tissues normally contain free radicals and reactive oxygen species, which are intrinsic to cell metabolism.  They serve useful purposes.  In excessive amounts, however, many believe they cause ”oxidative damage” and thereby contribute to chronic degenerative conditions such as atherosclerosis, aging, dementia, and cancer.

Antioxidants are thought to neutralize free radicals and reactive oxygen species, which may lead to better health.

The PREDIMED study is an ongoing Spanish project testing the heart-protective effects of the Mediterranean diet in high-risk people over the course of four years.  The three intervention groups are 1) Medi diet plus supplemental virgin olive oil, 2) Medi diet plus extra tree nuts, and 3) low-fat American Heart Association diet.

After three years of follow-up, the researchers measured “total antioxidant capacity” in the bloodstream of a subset of the PREDIMED participants.

They found that the two Mediterranean diet groups had significantly greater total antioxidant capacity, about 50% more than the low-fat control group.  Within the Medi + olive oil group, the participants with the highest levels of antioxidant capacity actually tended to lose weight, an association not seen in the other groups.

The Researchers’ Conclusions

Mediterranean diet, especially rich in virgin olive oil, is associatied with higher levels of plasma antioxidant capactiy.  Plasma total antioxidant capacity is related to a reduction in body weight after three years of intervention in a high cardiovascular risk population with a Mediterranean-style diet rich in virgin olive oil.

In other words, the Mediterranean diet with virgin olive oil may help you keep your weight under control, and the antioxidant capacity may contribute to the well-documented health benefits of the diet.

Steve Parker, M.D.

PS:  It’s impossible to tell from this report just how much weight loss was seen in the high-TAC Medi+olive oil subjects.  I doubt it was much.  Baseline body mass index for all participants was around 29, so they were overweight and just a shade under obese.

PPS:  Both the Ketogenic Mediterranean and Diabetic Mediterranean Diets mandate minimal amounts of olive oil consumption, with no upper limit.

Reference: Razquin, C., Martinez, J., Martinez-Gonzalez, M., Mitjavila, M., Estruch, R., & Marti, A. (2009). A 3 years follow-up of a Mediterranean diet rich in virgin olive oil is associated with high plasma antioxidant capacity and reduced body weight gain European Journal of Clinical Nutrition, 63 (12), 1387-1393 DOI: 10.1038/ejcn.2009.106

Dietitian Melanie Thomassian at her Dietriffic blog April 27, 2010, notes that nuts are not fattening, contrary to popular belief.  This is documented in a guest post by Matthew Denos.  Most of the evidence refers to almonds, so I’m not sure other nuts would be equally non-fattening. 

We’re talking about one or two ounces (up to 60 grams) a day.  Could someone gain fat weight eating more than that?  Probably, especially if they have a high-carbohydrate eating pattern.  Do I have scientific studies to back me up?  No. 

Nuts are a classic component of the traditional Mediterranean diet, which is one reason I included them in the Ketogenic Mediterranean Diet.  The other reason is that nut consumption is associated with lower heart disease risk.

Steve Parker, M.D.

It’s here.  It’s online.  It’s free.  It’s…

The Low-Carb Mediterranean Diet

For the last year I’ve been working on a comprehensive adaptation of the Mediterranean diet for people with type 2 diabetes and prediabetes.  Why?  Type 2 diabetics are prone to premature heart attacks, strokes, dementia, and death.  The Mediterranean diet, at least in the general population, prevents those illnesses and prolongs lifespan.  So the Mediterranean diet is a natural for diabetics.

But there’s a problem.  

The relatively high carbohydrate content of the traditional Mediterranean diet has the potential to raise blood sugar levels unacceptably high in people with diabetes.  High blood sugar levels are linked with worse health outcomes.  So, the Mediterranean diet without modification is a double-edged sword.  We’re caught between the horns of a dilemma.  [Insert favorite metaphor here.] 

Last fall, I designed the Ketogenic Mediterranean Diet which incorporates many of the healthy features of the Mediterranean diet while drastically reducing carbohydrate (carb) consumption.  High blood sugar levels drop significantly in most type 2 diabetes on the Ketogenic Mediterranean Diet. 

Many Ketogenic Mediterranean dieters are interested in expanding their carbohydrate options and consumption.  The Low-Carb Mediterranean Diet (LCMD) does that while aiming to control both excess weight and high blood sugar levels in diabetics, prediabetics, metabolic syndrome.  

Non-diabetics on the KMD may continue with it or move on to the LCMD if they wish. 

The Low-Carb Mediterranean diet is the world’s first published low-carbohydrate Mediterranean Diet, by the way.  How low-carb?  The KMD supplies about 5% of energy (calories) as carbohydrate; the LCMD goes to the 10–20% range.  [By way of reference, most people eat around 55% of total calories as carbs.] 

My goal a year ago was to help my personal patients with type 2 diabetes gain the health benefits of the traditional Mediterranean diet: longer lifespan and lower rates of heart attack, stroke, cancer, chronic lung disease, dementia, and Parkinsons disease, for example.  It’s my sincere hope that it benefits others as well.

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.

Update July 8, 2010:  I originally rolled out this new eating program in March, 2010, labelled as the Diabetic Mediterranean Diet, version 1.0.  I re-named it a few days ago. 

Nutrition scientists think that plants have small amounts of numerous “bioactive compounds,” more often referred to as phytonutrients, that protect us against disease.

Many scientific studies have looked at groups of people over time, noting the various foods they eat as well as the diseases they develop.  These are called epidemiologic, ecological, or observational studies.  One finding is that lower rates of heart disease, vascular disease, and cancer are seen in people consuming plant-based diets.  “Plant-based” isn’t necessarily vegetarian or vegan.  The traditional Mediterranean diet, for example, is considered by many to be plant-based because meat and poultry are not prominent compared to plants. 

In contemplating what source of carbohydrates a person with diabetes should eat, I’ve been reviewing the scientific literature to see which sources of carbs might provide the biggest bang for the buck in terms of health and longevity benefits.

Here are some quotes from a 2002 review article in the American Journal of Medicine:

Phenolic compounds, including their subcategory, flavonoids, are present in all plants and have been studied extensively in cereals, legumes, nuts, olive oil, vegetables, fruits, tea, and red wine. Many phenolic compounds have antioxidant properties, and some studies have demonstrated favorable effects on [blood clotting] and [growth of tumors]. Although some epidemiologic studies have reported protective associations between flavonoids or other phenolics and cardiovascular disease and cancer, other studies have not found these associations.

Hydroxytyrosol, one of many phenolics in olives and olive oil, is a potent antioxidant.

Resveratrol, found in nuts and red wine, has antioxidant, [anti-blood-clotting], and anti-inflammatory properties, and inhibits [malignant tumor onset and growth].

Lycopene, a potent antioxidant carotenoid in tomatoes and other fruits, is thought to protect against prostate and other cancers, and inhibits tumor cell growth in animals.

Organosulfur compounds in garlic and onions, isothiocyanates in cruciferous vegetables, and monoterpenes in citrus fruits, cherries, and herbs have [anti-cancer] actions in experimental models, as well as [heart-healthy effects].

In summary, numerous bioactive compounds appear to have beneficial health effects. Much scientific research needs to be conducted before we can begin to make science-based dietary recommendations. Despite this, there is sufficient evidence to recommend consuming food sources rich in bioactive compounds. From a practical perspective, this translates to recommending a diet rich in a variety of fruits, vegetables, whole grains, legumes, oils, and nuts.

The article discusses phytoestrogens—plant chemicals that act in us like the female hormone estrogen—but effects are complex and I suspect we know much more now than we did in 2002 .  Soy products are the best known source of phytoestrogens.

The traditional Mediterranean diet is rich in all of the foods mentioned above, except for tea.  Even the Ketogenic Mediterranean Diet includes the aforementioned foods except for tea (I need to add tea and coffee), cereals, and cherries.

Steve Parker, M.D.

Reference:  Kris-Etherton, P.M., et al.  Bioactive compounds in foods: their role in the prevention of cardiovascular disease and cancer.  American Journal of Medicine, 113 (2002. Supplement 9B): 71S-88S.

Age-related macular degeneration is the leading cause of blindness in Americans over 65.  Impaired vision precedes blindness.  A recent study linked consumption of omega-3 fatty acids with 30% lower risk of developing macular degeneration.  Believe me, it’s a lot better to prevent it than try to treat it once present. 

[I have a couple older relatives with macular degeneration, so I pay close attention to the scientific literature.]

What’s the best source of omega-3 fatty acids?  Our friend, the fish.  Especially cold-water fatty fish such as tuna, trout, sardines, herring, mackerel, halibut, and sea bass.  A few plants are also decent sources, but our bodies don’t utilize those omega-3 fatty acids as well as they do from fish.

Note that both the Advanced Mediterranean Diet and Ketogenic Mediterranean Diet feature fish.

Steve Parker, M.D.

Reference:  SanGiovanni, J.P., et al.  Long-chain polyunsaturated fatty acid intake and 12-y incidence of neovascular age-related macular degeneration and central geographic atrophy: AREDS report 30, a prospective cohort study from the Age-Related Eye Disease Study.  American Journal of Clinical Nutrition, 90 (2009): 1,601-1,607. First published October 7, 2009.   doi:10.3945/ajcn.2009.27594

Five servings of cod per week led to loss of an extra 3.7 pounds (1.7 kg) over eight weeks, according to a recent research report. 

European researchers noted that cod consumption in a prior study enhanced weight loss.  They wondered if that result could be reproduced, and whether the effect was “dose dependent.”  In other words, would those eating more cod lose more weight than those eating less?

They studied 125 subjects between the ages of 20 and 40, with body mass index between 27.5 and 32.5.  The abstract doesn’t mention sex of the participants.  They were all placed on calorie-restricted diets with identical percentages of protein, fat, and carbohydrate, and were followed for eight weeks.  Researchers divided the subjects into three groups:

1. One group was given 150 g (a little over 5 ounces)  of cod three times weekly
2. Another group was given 150 g cod five times weekly
3. The third group was given no seafood

Average weight loss overall was  11 pounds (5 kg).  The more cod consumed, the greater the weight loss.  Those eating five servings a week averaged 3.7 pounds (1.7 kg) more than the group not eating seafood. 

It’s unclear whether other types of fish would produce similar results.

These results support the prominent role of fish in the Ketogenic Mediterranean Diet. 

Steve Parker, M.D.

Reference:  Ramel, A., et al.  Consumption of cod and weight loss in young overweight and obese adults on an energy reduced diet for 8-weeks.  Nutrition, Metabolism and Cardiovascular Diseases, 19 (2009): 690-696.

I’ve been experimenting with a very low-carb ketogenic diet that incorporates elements of the Mediterranean diet.  This is a progress report. 

Body Stats

My weight is 155 lb (70.5 kg) now compared with 160.5 at the end of Week 4.  I started this plan at 170 lb (77.3 kg) and a waist circumference of 36.5 inches.  I seem to have plateaued around 155 over the last few weeks.  Waist circumference is 34.25 inches, down an inch over the last three weeks.  This is a pretty good weight for me.

What am I eating? 

Ninety percent of my food consists of:

eggs (3/day), mozarella string cheese sticks, nuts (almonds, mixed, peanuts), steak, sausage, hamburger, chicken, canned tuna, canned sardines, tomatoes, onions, avocadoes, cucumbers, baby spinach, celery, romaine lettuce, red wine (7 fl oz/day), extra virgin olive oil, sugar snap peas, butter, Italian vinaigrette dressing, mayonnaise (on tuna), salt, pepper.  [I should eat greater variety of vegetables and nuts.]

Nutrient Analysis  (thanks to NutritionData.com)

Average daily calories: 1,800

Macronutrient percentages: 8% carbohydrate, 30% protein, 53% fat, 9% alcohol

Daily digestible carbohydrates: 25 g

Daily fats: 110 g total fat, 31 g saturated fat, 52 g monounsaturated fats

Daily cholesterol: 800 mg (mostly from eggs)

Daily fiber: 7-10 g

Daily sodium: 1,500 mg (not counting salt from shaker)

Any potential micronutrient deficiencies? 

Yes.  Considering the amounts of the various foods I’m eating, the un-supplemented Ketogenic Mediterranean Diet on many, if not most, days would be deficient in vitamins D, E, K, thiamin, folate, and pantothenic acid, and the minerals calcium, iron, magnesium, potassium, sodium, copper, manganese.  Less often, there are deficiencies of zinc and vitamins A, C, B12, riboflavin, and B6.  [I am using table salt from the shaker but not tracking it; sodium deficiency is very unlikely.]

These potential deficiencies are based on the % Daily Values recommended by the U.S. Food and Drug Administration for a healthy adult eating 2,000 calories daily.  Someone following the Ketogenic Mediterranean Diet but eating a different mixture of foods could have a better or worse micronutrient profile.

Version 1.01 of the Ketogenic Mediterranean Diet from the outset recommended one daily Centrum multivitamin/multimineral supplement, plus extra vitamin D 400 IU/day, and elemental calcium 500-1,000 mg/day.  These would prevent a large majority of these potential deficiencies. 

I started a daily magnesium supplement a week ago to suppress nocturnal leg cramps.  It’s working well.

Implications

I’m in the midst of revising my recommended supplements and will post them here within the next few days.  I’m likely to add magnesium, potassium, table salt, and fiber. 

Remember, this is not a life-long eating plan; it’s a temporary weight-loss program.  Natural sources of vitamins and minerals along with phytonutrients will be added later.

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, nutritional supplement, or exercise changes.

Today I’m starting a very low-carb diet, the Ketogenic Mediterranean Diet, to lose only about 10 lb (4.55 kg) of fat I’ve accumulated around my waist over the last six months. I gained the weight intentionally, so I’d have something to experiment on.  Cookies, candy bars, ice cream, cinnamon rolls and other pastries, pies, cakes, fried pies, french fries, shakes and malts—all these reliably put extra weight on me.  It’s not been a burden to gain the weight.  I did it for Science!

My current stats

Weight: 170 lb (77.3 kg)

Height: 71 inches (180 cm)

Body mass index: 23.8

Waist circumference: 36.5 inches (92.7 cm)

Usual  caloric intake: 2400/day (from prior self-experimentation and food diaries)

Activity level:  somewhat active

Health status:  Good.  No trouble with high cholesterol or trigylcerides, diabetes, heart disease, high blood pressure.

Comments

My body mass index is in the healthy range, so the 10 pounds I want to lose are “vanity pounds.”  You wouldn’t call me fat.  Maybe “a little chubby.”  My daughter and mother both spontaneously mentioned the excess weight to me.  My usual adult weight is around 160 pounds.  I dropped to 148 once through caloric restriction; my wife thought that was too low. 

My Plans

I’ll report daily at the Diabetic Mediterranean Diet Blog regarding my weight, dietary transgressions, exercise, random thoughts, etc.  Check under the category “My KMD Experience” if you want to follow along. 

If it’s not too much hassle, I’ll track my food intake at NutritionData.com and share the nutritional analysis weekly.  I’m hoping I don’t get too busy to keep this up.

Steve Parker, M.D.