Advanced Mediterranean Diet

It’s estimated that the Old Stone Age diet provided much more omega-3 fatty acids and much less omega-6s, compared to modern Western diets.  This may have important implications for development of certain chronic diseases like cancer and heart disease. 

Fatty acids, by the way, refer to the long chains of molecules that comprise the majority of fats and oils.

Some folks speculate that the Stone Age (Paloelithic) diet may be the healthiest way to eat because our genes are adapted to it.  In other words, we evolved in a certain food environment over hundreds of thousands of years, so we should have optimal health if we follow our ancestral diet (whatever that is). 

A major change in human eating habits over the last century has been the dramatic increase in consumption of industrial seed oils like corn and soybean oil.  These have dramatically increased the omega-6 fatty acids in our diets. i.e., they’v3e increased the omega-6/omega-3 ratio.  Another major change starting about 10,000 years ago is the increase in consumption of grains.

This’ll improve your omega-6/omega-3 ratio!

I haven’t studied omega-6/omega-3 ratio issue in great detail but hope to do so at some point.  Evelyn Tribole has strong opinions on it; I may get one of her books.

I saw an online video of William E.M.Lands, Ph.D., discussing the omega-6/omega-3 ratio.  He mentioned free software available from the National Insitutes of Health that would help you monitor and adjust your ratio.

You can see the video here.  Dr. Lands’ talk starts around minute 12 and lasts about 45 minutes.  He says it’s just as important (if not more so) to reduce your omega-6 consumption as to increase your omega-3.  And don’t overeat.

Steve Parker, M.D.

Italian researchers reviewed the medical/nutrition literature of the last three years and confirmed that the Mediterranean diet 1) reduces the risk of death, 2) reduces  heart disease illness and death, 3) cuts the risk of getting or dying from cancer, and 4) diminishes the odds of developing dementia, Parkinsons disease, stroke, and mild cognitive impairment.

These same investigators published a similar meta-analysis in 2008, looking at 12 studies.  Over the ensuing three years (as of June, 2010), seven new prospective cohort studies looked at the health benefits of the Mediterranean diet.  The report at hand is a combination of all 19 studies, covering over 2,000,000 participants followed for four to 20 years.  Nine of the 19 Mediterranean diet studies were done in Europe.

The newer studies, in particular, firmed up the diet’s protective effect against stroke, and added protection against mild cognitive impairment.

So What?

The Mediterranean diet: No other way of eating has so much scientific evidence that it’s healthy and worthy of adoption by the general population.  Not the DASH diet, not the “prudent diet,” not the American Heart Association diet, not vegetarian diets, not vegan diets, not raw-food diets, not Esselstyne’s diet, not Ornish’s diet, not Atkins diet, not Oprah’s latest diet, not the Standard American Diet, not the  . . . you name it. 

Not even the Low-Carb Mediterranean Diet.

Just as important, the research shows you don’t have to go full-bore Mediterranean to gain a health and longevity benefit.  Adopting  just a couple Mediterranean diet features yeilds a modest but sigificant gain.  For a list of Mediterranean diet components, visit Oldways or the Advanced Mediterranean Diet website. 

Steve Parker, M.D.

Reference:  Sofi F, Abbate R, Gensini GF, & Casini A (2010). Accruing evidence about benefits of adherence to the Mediterranean diet on health: an updated systematic review and meta-analysis. The American journal of clinical nutrition PMID: 20810976

Type 2 diabetes is associated with higher incidence of several cancers: liver, pancreas, uterus, colo-rectal, breast, and bladder.  On a brighter note, diabetics have lower risk of prostate cancer.

That’s about all we know for sure, according to a report from an expert panel convened by the American Diabetes Association and the American Cancer Society and published recently in CA: A Cancer Journal for Clinicians.

The report is focused on type 2 diabetes simply because 95% of all worldwide cases of diabetes are type 2; we have much more data.  [Type 1 diabetes, you may recall, has onset much earlier  in life and is fatal if not treated with insulin injections.  The type 1 pancreas produces no insulin.]

This report is a good summary of all we know about the cancer/diabetes connection in 2010.  What we don’t know far outweighs what we do know.

Does optimal treatment of diabetes reduce cancer risk?  Do particular diabetic medications raise or lower the risk of cancer?  If an overweight diabetic loses excess weight, does the risk of cancer diminish?  Sorry . . . we don’t know.

In men, 25% of all invasive cancers in the U.S. will be prostate cancer.  In women, breast cancer is the leader, comprising 26% of all cancers.  [Common skin cancers are rarely invasive or fatal and are not included in these statistics.  Melanoma, on the other hand, is invasive.]

The lifetime probability of an individual developing invasive cancer in the U.S. is about 4 in 10 (40%).  A little higher in men (45%), a little lower in women (38%).  The American Cancer Society projected 565,650 deaths from cancer in 2008.  If we look at deaths of people under 85, cancer kills more people than heart disease.

The traditional Mediterranean diet is associated with less risk of prostate, breast, colon, and uterus cancer.  Two of these, you’ll note, are seen at higher rates in diabetics.

Lack of regular exercise is associated with higher cancer rates. 

If I were a type 2 diabetic wanting to reduce my risk of cancer, I’d be sure to exercise regularly, keep my body mass index under 30 (if not lower), consider a Mediterranean-style diet, and ask my doctor to monitor for onset of cancer.

Steve Parker, M.D., author of The Advanced Mediterranean Diet

Reference: Giovannucci, E., Harlan, D., Archer, M., Bergenstal, R., Gapstur, S., Habel, L., Pollak, M., Regensteiner, J., & Yee, D. (2010). Diabetes and Cancer: A Consensus Report CA: A Cancer Journal for Clinicians DOI: 10.3322/caac.20078

A study in the current issue of the American Journal of Clinical Nutrition associates the Mediterranean diet with lower risk of breast cancer in postmenopausal Greek women.

The evidence is from the Greek portion of the massive EPIC study: European Prospective Investigation Into Cancer and nutrition.  Investigators followed almost 15,000 women for 10 years.  No protective effect was seen for premenopausal women eating Mediterranean-style. 

The study at hand adds to prior evidence that the Mediterranean diet seems to protect against cancer of the breast, prostate, uterus, and colon/rectum.

Steve Parker, M.D.

Reference: Trichopoulou, A., Bamia, C., Lagiou, P., & Trichopoulos, D. (2010). Conformity to traditional Mediterranean diet and breast cancer risk in the Greek EPIC (European Prospective Investigation into Cancer and nutrition) cohort American Journal of Clinical Nutrition DOI: 10.3945/ajcn.2010.29619

Red meat and processed meat consumption are associated with “modest” increases in overall mortality and deaths from cancer and cardiovascular disease, according to National Institutes of Health researchers.  This goes for both sexes.

Data are from the huge NIH-AARP Diet and Heart Study, a prospective cohort trial involving  over 550,000 U.S. men and women aged 50-71 at the time of enrollment.  Food consumption was determined by questionnaire.  Over the course of 10 years’ follow-up, over 65,000 people died.  Investigators looked to see if causes of death were related to meat consumption.

What do they mean by red meat, processed meat, and white meat?

Red meat:  all types of beef and pork [wasn’t there a U.S. ad campaign calling pork “the other white meat”?]

White meat:  chicken, turkey, fish

Processed meat:  bacon, red meat sausage, poultry sausage, luncheon meats (red and white), cold cuts (red and white), ham, regular hotdogs, low-fat poultry hotdogs, etc.

What did they find?

See the first paragraph above.

Studies like this typically look at the folks who ate the very most of a given type of food, those who ate the very least, then compare differences in deaths between the two groups.  That’s what they did here, too.  For instance, the people who ate the very most red meat ate 63 grams per 1000 caories of food daily.  Those who ate the least ate 10 grams per 1000 cal of food daily.  That’s about a six-fold difference.  Many folks eat 2000 calories a day.  The high red meat eaters on 2000 cals a day would eat 123 grams, or 4.4 ounces of red meat.  The low red meat eaters on 2000 cals/day ate 20 grams, or 0.7 ounces.

The heavy consumers of processed meats ate 23 grams per 1000 cal of food daily.  The lowest consumers ate 1.6 grams per 1000 cal.

Comparing these two quintiles of high and low consumption of red and processed meats, overall mortality was 31-36% higher for the heavy red meat eaters, and 16-25% higher for the heavy processed meat eaters.  [The higher numbers in the ranges are for women.]  Similar numbers were found when looking at cancer deaths and cardiovascular deaths (heart attacks, strokes, ruptured aneurysms, etc).

It’s not proof that heavy consumption of red and processed meats is detrimental to longevity, but it’s suggestive.  The “Discussion” section of the article reviews potential physiological mechanisms for premature death.

The researchers called these differences “modest.”  I guess they use “modest” since most people eat somewhere between these extreme quintiles.  The numbers incline me  to stay out of that “highest red and processed meat consumer” category, and lean more towards white meat and fish.

The traditional Mediterranean diet and Advanced Mediterranean Diet are naturally low in red and processed meats.

Steve Parker, M.D. 

Reference:  Sinha, Rashmi, et al.  Meat intake and mortality: a prospective study of over half a million people.  Archives of Internal Medicine, 169 (2009): 562-571.

The traditional Mediterranean diet has long been associated with longer lifespans and lower rates of chronic diseases: heart disease, strokes, dementia, and cancer (breast, prostate, lung, uterus).  Recent research has expanded the benefit list.

I ran across a good summary of the health benefits of Mediterranean-style eating at Medical News Today, published online May 6, 2009.  An excerpt:

The following health benefits have been observed by people who have a Mediterranean diet:

• Longer lifespan
• Lower risk of dying at any age
• Lower risk of dying from heart disease
• Lower risk of dying from cancer
• Lower risk of developing Type 2 diabetes
• Lower risk of hypertension (high blood pressure)
• Lower risk of raised cholesterol levels
• Lower risk of becoming obese
• Lower risk of developing Alzheimer’s disease

Not mentioned above is the lower risk of Parkinson’s Disease and chronic obstructive pulmonary disease.  You’ll also find a fair description of the traditional Mediterranean diet.

Steve Parker, M.D.

We’ve been told by the authorities repetitively that eating plenty of fruits and vegetables will lower our risk of cancer.  [As in my last blog post.]  However, a recent study in the American Journal of Clinical Nutrition, says that ain’t so.

Fire up the grill—we’re havin’ steak tonight!

Researchers looked at data from over 450,000 participants (men and women over 50) in the National Institutes of Health—AARP Diet and Health Study.  Diet data was collected by self-administerd questionnaire.  State-level cancer registries identified the cancers that developed during the average follow-up of seven years.

Their conclusions and selected comments:

Intake of fruit and vegetables was generally unrelated to total cancer incidence in this cohort.

However, on the basis of animal studies, human case control and cohort studies, and randomized controlled trials, there is likely no harm associated with the consumption of fruit and vegetables and their consumption may prevent cardiovascular disease.

Indeed, analyses in this cohort and in others that have investigated dietary patterns rich in fruit and vegetables have found reduced risks of colorectal cancer [three references cited] and mortality, including death from cardiovascular disease and all cancers [one reference was cited supporting reduced deaths from CVD and all cancers—a Mediterranean diet study].

As in all good science reports, the researchers compare and contrast their findings with similar published research.  They note that theirs is one of only four large cohort studies that have examined this issue.  Two of the other three (see references below) also found no association between total cancers and fruit and vegetable consumption.  The one that did find a beneficial linkage was the smallest of the four, so not as compelling.

Before this research was published, some experts suggested that adequate fruit and vegetable intake could prevent between 5 and 12% of cancers.

Eat your fruits and vegetables because they taste good, provide myriad nutrients, and may have some other healthful properties.  But not to lower overall cancer risk.  

Steve Parker, M.D.

References:

George, Stephanie, et al.   Fruit and vegetable intake and risk of cancer: a prospective cohort study.  American Journal of Clinical Nutrition, 89 (2009): 347-353. 

Hung, H.C., et al.  Fruit and vegetable intake and risk of major chronic disease.  Journal of the National Cancer Institute, 96 (2004): 1,577-1,584.

Takachi, R., et al.  Fruit and vegetable intake and risk of total cancer and cardiovascular disease [in Japan].  American Journal of Epidemiology, 167 (2008): 59-70.

Benetou, V., et al.  Vegetables and fruit in relation to cancer risk: evidence from the Greek EPIC Cohort Study.  Cancer Epidemiology, Biomarkers, and Prevention, 17 (2008): 387-392.

How many times have you heard how important it is to eat fruits  and vegetables?  Now, is it five or nine servings a day?  Why are fruits and veggies always lumped together?  What does a watermelon have in common with spinach?

The author of a 2004 article in the Journal of Postgraduate Medicine answered some of these questions.  Here are a few quotes from from the summary:

The intake of 400-600 g/d of fruits and vegetables is associated with reduced incidence of many common forms of cancer, and diets rich in plant foods are also associated with a reduced risk of heart disease and many chronic diseases of ageing.

These foods contain phytochemicals that have anti-cancer and anti-inflammatory properties which confer many health benefits. Many phytochemicals are colourful, and recommending a wide array of colourful fruits and vegetables is an easy way to communicate increased diversity of intake to the consumer. For example, red foods contain lycopene, the pigment in tomatoes, which is localized in the prostate gland and may be involved in maintaining prostate health, and which has also been linked with a decreased risk of cardiovascular disease. Green foods, including broccoli, Brussels sprouts and kale, contain glucosinolates which have also been associated with a decreased risk of cancer. Garlic and other white-green foods in the onion family contain allyl sulphides which may inhibit cancer cell growth. Other bioactive substances in green tea and soybeans have health benefits as well.

Consumers are advised to ingest one serving of each of the seven colour groups daily, putting this recommendation within the United States National Cancer Institute and American Institute for Cancer Research guidelines of five to nine servings per day. Grouping plant foods by colour provides simplification, but it is also important as a method to help consumers make wise food choices and promote health.

Asking U.S. consumers to eat one serving from each of seven fruit and vegetable color groups daily is a bit much.  I don’t see that happening.  But the suggestion is a start.  Darya Pino (Summer Tomato blog) probably does it every day, but I don’t know any others.  My simplified message: Eat a variety of colorful fruits and veggies daily.

Note that the very low-carb Ketogenic Mediterranean Diet provides 400 grams of vegetables and fruits daily, and I count seven colors (assuming you allow me to include black olives).  On the KMD document I list avocado, cucumber, and tomato under “vegetables,” but they are indeed fruits.  Heck, I guess olives are fruit, too.

“So, what’s your point, Parker,” you might well ask.  I don’t expect anyone to follow the Ketogenic Mediterranean Diet for life.  When it’s time to move on to a “Diabetic Mediterranean Diet,” I’m considering adding more options: traditional fruits and some colorful vegetables like purple beets, yellow corn, and orange carrots and sweet potatoes.

I still don’t know why “fruits and vegetables” are joined at the hip.  Legumes, grains, and dairy products all rate their very own category.  It’s just not fair.

Steve Parker, M.D.

Reference:  Heber, D.  Vegetables, fruits and phytoestrogens in the prevention of diseases.  Journal of  Postgraduate Medicine, 50 (2004): 145-9.

Update: March 8, 2010

Beth at Weight Maven blog put together a colorful graphic showing the major foods and phytonutrients associated with particular colors, based on Dr. Heber’s work.

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.

Cooking doesn’t destroy much of olive oil’s healthy properties, according to registered dietitian Karen Collins in a recent guest post at CalorieLab.

I’ve been wondering about this since olive oil plays such a prominent role in the Advanced Mediterranean and Ketogenic Mediterranean Diets.  I use room-temperature olive oil on my salads and vegetables, but also use it to sauté vegetables, eggs, and meat. 

Olive oil is the major fat in the traditional Mediterranean diet.  It has heart-healthy and perhaps anti-cancer action related to monounsaturated fat and phenolic compounds that have antioxidant and anti-inflammatory properties.

Steve Parker, M.D.