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The Mediterranean Eating Pattern

A Closer Look at the Research

Primary Care Dietitians’ Association Presents

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The Mediterranean Eating Pattern

Evidence for health benefits of the Mediterranean Eating Pattern (MedDiet)
Elements of a MedDiet

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Evidence Quality

Highest Quality

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Lowest

Quality

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Considerations of MedDiet Studies

Researchers and subjects from mostly white or European countries

Other cultural diets not studied as frequently

May not be generalizable across racial and ethnic groups

There is no one MedDiet .. it is a set of characteristics

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Meta-analyses of 12 Cohort Studies�1966-2008

Mediterranean Diet Score Tools used to assess adherence

1.5 million healthy subjects: 40,000 fatal & non-fatal events

a 2-point increase in adherence to a Mediterranean diet:

9% reduction in overall death
9% reduction in death from cardiovascular diseases (CVD)
6% reduction in incidence of or death from cancer
13% reduction in incidence of Parkinson’s disease and Alzheimer’s

Sofi F, Cesari F, Abbate, R, Gensini Gf, Casini A. (2008). Adherence to Mediterranean Diet and Health Status: Meta-Analyses .

BMJ Online First 2008;337:a1344: 1-7.

Sofi F, Abbate R, Gensini GF, Casini A. (2010). Accuring Evidence on Benefits of Adherence to the Mediterranean on Health: An

Updated Systematic Review and Meta-Analysis Am J Clin Nutr Nov:92(5):1189-96. doi: 10.3945/ajcn.2010.29673. Epub 2010 Sep 1.

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2014: Updated Meta-analyses�18 Cohort Studies

4.1 million subjects not present in previous meta-analyses

a 2-point increase in adherence to a Mediterranean diet

8% reduction in overall death
10% reduction in death from cardiovascular diseases (CVD)
4% reduction in incidence of or mortality from cancer

Sofi F, Macchi C, Abbate P, Gensini GF, Casini A (2014). Mediterranean diet and Health status: an updated meta

analysis and proposal for a literature based adherence score Public Health Nutr 17(12);2769-2782.

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CVD: Randomized Controlled Trial�PREDIMED

10 primary care centers, 5 year randomized controlled trial (RCT), ~7,500 people

Estruch R, Rose E, Salas-Savlaldo J, Covas, MI, Corella D, Aro F, Gomez-Gracia E, Ruiz-gutierrez V, Fiol M, Lapetra J, Lamuela-Raventose RM (2018). Primary Prevention of cardiovascular disease with a Mediterranean diet supplemented with extra virgin olive oil and nuts. N Engl J Med, 2018 Jun 21: 378 (25): 2441-2442. doi:10.1056/NEJMoa1800389

The PREDIMED [PREvención con DIeta MEDiterránea] study was the first large multicentre randomised controlled trial (RCT) of the MedDiet. It was designed to assess the long-term effects of this eating pattern without any energy restriction, on the incidence of CVD in individuals at high cardiovascular risk. You may recall this study was retracted in June 2018 and republished due to problems with the randomization procedure. However, a reanalysis of the data without these participants did not materially change the results.

You can see here the subject characteristics. They were determined to be high risk for CVD if they had T2DM or 3 or more CVD risk factors as listed here. They were then randomized to one of three protocols: MedDiet plus EVOO, MedDiet plus nuts, or control diet (low fat).

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CVD: Randomized Controlled Trial�PREDIMED

MedDiet with EVOO or nuts

reduced incidence of CVD events by 30%

(even in patients at high risk of CVD)

Estruch R, Rose E, Salas-Savlaldo J, Covas, MI, Corella D, Aro F, Gomez-Gracia E, Ruiz-gutierrez V, Fiol M, Lapetra J, Lamuela-Raventose RM (2018). Primary Prevention of cardiovascular disease with a Mediterranean diet supplemented with extra virgin olive oil and nuts. N Engl J Med, 2018 Jun 21: 378 (25): 2441-2442. doi:10.1056/NEJMoa1800389

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Diabetes Prevention: PREDIMED sub-study

4 year RCT, multi-site, in Spain

Diabetes incidence in:

MedDiet/EVOO was 10%
MedDiet/nuts was 11%
Control low fat diet was 18%

When both MedDiet group data was pooled, diabetes incidence was reduced by 52%

Salas-Salvado J et al. (2011). Reduction in the Incidence of Type 2 Diabetes with the Mediterranean Diet: Results of the

PREDIMED-Reus nutrition intervention trial. Diabetes Care 2011 Jan: 34(1): 14-19.

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Kidney Health: Cohort Study

750 people: kidney function assessment and diet assessment – MedDiet score 0 – 9

MedDiet score >=5/9 associated with significant protection (50% reduced risk of declining kidney function)

Every 1-point increase in MedDiet score = 12% reduced risk of declining kidney function

Higher adherence to MedDiet associated with lower progression of chronic kidney disease

Khatri M. et al. (2014). The association between a Mediterranean-Style diet and kidney function in the Northern Manhattan study cohort. Clin J Am Soc Nephrol 9:1868-1975

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Metabolic Syndrome: Meta-analyses of 50 studies (35 RCTs, 13 cohort)

534,906 individuals
Metabolic syndrome – 3/5

High waist measure
High triglycerides
Low good cholesterol
High fasting blood sugar
High blood pressure

Kastorini CM, Milonis HJ, Esposito K, Guigliano D, Goudevenous JA, Panagiotakos DB (2011). The Effect of Mediterranean Diet on Metabolic Syndrome and it’s components: a meta-analyses of 50 studies and 534,906 individuals. J Amer College of Cardio 57(11),1299-313.

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Metabolic Syndrome: Meta-analyses of 50 Studies (35 RCTs, 13 cohort)

534,906 individuals
Metabolic syndrome – 3/5

High waist measure
High triglycerides
Low good cholesterol
High fasting blood sugar
High blood pressure

MedDiet associated with reduced risk of

metabolic syndrome by 31%

Kastorini CM, Milonis HJ, Esposito K, Guigliano D, Goudevenous JA, Panagiotakos DB (2011). The Effect of Mediterranean Diet on Metabolic Syndrome and it’s components: a meta-analyses of 50 studies and 534,906 individuals. J Amer College of Cardio 57(11),1299-313.

RCTs showed protective effect of MedDiet on all metabolic syndrome factors

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Healthier Pregnancy & Baby

Systematic Review of cohort studies

Lower risk of high blood pressure associated with pregnancy (pre-eclampsia)

Lower risk of pre-term birth

Cohort Study

Higher adherence to MedDiet
32% lower risk of having children with a growth curve above expectations

The association between dietary factors and gestational hypertension and pre-eclampsia: a systematic review and meta-analysis of observational studies. BMC Med. 2014; 12: 157.

The Association of Mediterranean Diet during Pregnancy with Longitudinal Body Mass Index Trajectories and Cardiometabolic Risk in Early Childhood. The Journal of Pediatrics, 2018.

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Depression: Meta-analyses�22 Cohort Studies

17,175 participants

2,092 cases of depression

Higher MedDiet score associated with 32% reduced risk of depression

Interpretation

“Adherence to a Mediterranean diet may contribute to the prevention of a series of brain diseases; this may be of special value given the aging of Western societies”

Psaltopoulou T et al (2013). Mediterranean Diet, Stroke, Cognitive Impairment, Depression, A Meta-Analysis Ann Neurol May 2013;74:580–591

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Depression: Randomized Control Trial

67 people with moderate depression
Randomized for 12 weeks

Half to MedDiet + 7 dietitian sessions
Half to control + 7 social support sessions

Improved depression scores in MedDiet group vs controls

A randomised controlled trial of dietary improvement for adults with major depression (the ‘SMILES’ trial). BMC Med. 2017 Jan 30;15(1):23.

This 2017 RCT investigated if a Med eating pattern approach was an effective treatment option for moderate to severe depression. 67 participants with moderate depression were randomized into 2 groups. The intervention group had seven one-hour individual nutrition consulting sessions delivered by a dietitian. This involved education on the Med eating pattern and counselling including motivational interviewing, goal setting and mindful eating. The control condition was a social support protocol to the same visit schedule and length where neutral topics were discussed. After 12 weeks, the intervention group showed significant reductions in depression symptoms over the control group as measured by Montgomery-Asberg Depression Rating Scale. [speaker note: MADRS is a ten-item diagnostic questionnaire which psychiatrists use to measure the severity of depressive episodes in patients with mood disorders.]

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Cognitive Impairment

Psaltopoulou T et al (2013). Mediterranean Diet, Stroke, Cognitive Impairment, Depression, A Meta-Analysis Ann Neurol May 2013;74:580–591

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Cognitive Impairment:�Systematic Review (22 cohort studies)

Adherence to MedDiet associated with reduced risk of stroke, depression, cognitive impairment and Parkinson’s

10,275 patients with 1278 cases of cognitive impairment

Higher adherence to MedDiet associated with:

40% decr. risk cognitive impairment in 8 studies
57% decr. Alzheimer’s in 4 studies

Moderate adherence to MedDiet 21% decr. risk for cognitive impairment

Psaltopoulou T et al (2013). Mediterranean Diet, Stroke, Cognitive Impairment, Depression, A Meta-Analysis Ann Neurol May 2013;74:580–591

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Cognition over time:�Systematic Review (18 cohort studies)

Mediterranean Diet Adherence

Slowed rates of:

cognitive decline
conversion to Alzheimer’s

Improved functioning

Memory
Visual perceptions
Executive functioning (problem solve, plan, organize)

Hardman et al (2016). Adherence to the Mediterranean–style diet and effects on cognition in adults: Qualitative Evaluation and

Systematic Review of Longitudinal and Prospective Trials Front Nutr; 3:22.

“The utilization of a dietary pattern, such as the MedDiet, will be essential as part of the medical resources to maintain quality of life and reduce the potential social and economic burden of dementia.”

Another systematic review looked at changes in cognition over time, and found better adherence to a Med eating pattern was associated with slower rates of cognitive decline and conversion to Alzheimer’s; as well as improvements in memory, visual perceptions, problem solving, planning and organizing. The study authors even went so far as to equate the MedDiet as an essential medical resource to help maintain quality of life and reduce the potential burdens of dementia.

A mechanism for these effects may be related to the gut microbiome. A study of older individuals published in 2020 found a Med diet intervention caused gut microbiome changes linked to improvements in cognitive function and memory. Gut microbiome research is really in its infancy, so look out for more studies on the Mediterranean eating pattern and the gut microbome in the future. [Mediterranean diet intervention alters the gut microbiome in older people reducing frailty and improving health status: the NU-AGE 1-year dietary intervention across five European countries. http://dx.doi.org/10.1136/gutjnl-2019-319654]

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Mortality risk

Cardiovascular disease

Cancer incidence

Alzheimer’s, Parkinson’s

Cognitive decline

High blood pressure

LDL (bad) cholesterol

Type 2 diabetes risk

Depression

Healthier pregnancy

Healthier baby

Mediterranean Eating Pattern Benefits

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MedDiet & Clinical Practice Guidelines

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What is a Mediterranean Diet Eating Pattern?

What is a Mediterranean Diet

Eating Pattern?

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A Mediterranean Diet Isn’t...

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A Mediterranean Diet Is ...

... based on traditional foods from countries that surround the Mediterranean Sea

Crete, Greece and S. Italy in 1950’s/60’s – highest life expectancy & lowest chronic disease rates

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Enjoy meals with family and friends
Choose homemade, whole foods, most often
Limit ultra-processed foods

It’s a Lifestyle!

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The MedDiet Eating Pattern

High	Moderate	Low
Olive oil	Dairy (fermented: cheese, yogurt)	Red meat
Vegetables and Fruit	Poultry/eggs	Processed meats
Whole grains	Alcohol (mainly red wine with meal)	Sweets
Nuts & Seeds
Legumes
Fish (emphasis on fatty fish)

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Mediterranean Diet Pyramid

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MedDiet Possible Mechanisms

High in good sources of fat (monosaturated) and low in saturated fat and trans fat
High in complex carbs – whole grains and legumes
High in fibre – soluble and insoluble
High in beta carotene, Vitamin E, Vitamin C, magnesium, potassium, phenols and antioxidants

These factors help to:

Improve blood cholesterol, blood pressure, insulin resistance
Keep our arteries healthy and more elastic
Reduce inflammatory markers

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Moving Towards a Mediterranean Diet�

Take small steps, one change at a time
It’s not all or nothing
Our destination …. a better dietary pattern for your best health
Can’t get there without knowing where ‘there’ is
Requires:

access
adaptability
incremental progress

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Assessing Your Current Diet

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Questions?

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Thank you for joining!

For more Mediterranean Diet resources please visit: https://primarycaredietitianassociation.org/resources/public-resources/