For approximately 300,000 years, Homo sapiens have consumed a vast array of foods from all sources deemed edible. From plants, grains, and fruits to various animal parts—everything that roams, flies, swims, or crawls has passed through our digestive systems. Given this extensive history, one might assume that we would have identified an optimal diet for health. Yet here we are, millennia later, debating the merits of low-carb, ketogenic, carnivore, low-fat, vegan, and flexitarian diets, alongside intermittent fasting and numerous others. Among all this dietary confusion, the scientific community has shown significant enthusiasm for the “Mediterranean Diet.” But therein lies a complication: the Mediterranean region comprises twenty-one countries, each with its own unique culinary traditions. Spaniards, for example, eat differently than the Lebanese, and a French baguette is not comparable to Greek pita. So, what exactly is the “Mediterranean Diet” that experts advocate so vigorously? And what makes it stand out?
Life expectancy in the Mediterranean area is generally higher than in North America, particularly in Southern European nations like Spain, Italy, and Greece, which also report lower rates of heart disease and obesity. The populations in these countries demonstrate better metabolic health, indicated by optimal levels in five health markers: waist circumference, fasting glucose, triglycerides, HDL cholesterol, and blood pressure, all without reliance on medication. While diet certainly plays a role, lifestyle factors also contribute significantly. People in the Mediterranean region tend to walk more, engage in social connections, and have access to quality healthcare.
If we consider diet a key factor, we must examine what these Mediterranean populations actually consume. Generally, their diets are rich in vegetables, fruits, whole grains, legumes, nuts, seeds, and fish. They limit red meat consumption, moderate their intake of dairy (primarily yogurt), and include poultry and eggs. A hallmark of their cuisine is the use of olive oil as the primary fat source. However, perhaps the most crucial aspect of their diet may be what they intentionally avoid: ultraprocessed foods, refined carbohydrates, processed meats, and sugary beverages. This eating pattern helps lower LDL cholesterol and blood pressure, diminishes inflammation, enhances insulin sensitivity, and increases feelings of fullness, resulting in reduced calorie intake.
Establishing any genuine benefits of the Mediterranean diet necessitates more than observational studies. It requires robust, randomized intervention trials, such as the “PREDIMED” trial conducted in Spain from 2003 to 2011. This study involved 7,500 adults at high risk for heart disease, divided into three groups. One group followed the Mediterranean diet with additional olive oil, another adhered to the Mediterranean diet with extra nuts, and the last followed a low-fat control diet. After five years, the groups consuming the Mediterranean diet witnessed a remarkable 30% reduction in major cardiovascular events such as heart attacks, strokes, or cardiovascular-related deaths. Quite impressive!
What about cancer? The differences are not as significant but some cancers, like colon and breast cancer, have a slightly lower incidence in Mediterranean countries compared to North America. This may be attributed to higher fiber and antioxidant intake from their vegetable-rich diets. Another vital area to explore regarding the Mediterranean diet is its impact on mental health.
Insight into this can be gained from a study examining adherence to the “MIND” diet, which is believed to promote brain health. The MIND diet merges the principles of the Mediterranean Diet and the “DASH” (Dietary Approaches to Stop Hypertension) diet. Researchers monitored 1,600 adults aged 60 and above who filled out food frequency questionnaires and underwent MRI scans every four years. Dietary intake was assessed using the “MIND Scoring System,” which allocates points for servings of “brain-healthy” foods over a week, while deducting points for servings of “brain-unhealthy” foods. Brain-healthy foods include leafy greens, various vegetables, berries, nuts, olive oil, whole grains, fish, poultry, beans, legumes, and wine. In contrast, the brain-unhealthy foods comprise meat and meat products, butter and margarine, cheese, pastries, sweets, fast foods, and fried foods.
Participants calculating their adherence to the MIND diet score points as follows: +1 point for consuming a serving of brain-healthy foods, –1 point for servings of brain-unhealthy foods based on the table below. A moderate intake awards 0.5 points, while a low intake of healthy foods or a high intake of unhealthy foods results in 0 points. For instance, consuming six or more servings of leafy green vegetables weekly earns 1 point, while three servings yield half a point. With a total of 15 categories, the maximum score is 15.
Those who adhered closely to the MIND diet experienced less brain shrinkage and a reduction in grey matter loss, crucial for memory and cognition. Unfortunately, the study did not include memory tests to ascertain if reduced brain shrinkage corresponded with improved memory. Both brain shrinkage and grey matter regression are linked to Alzheimer’s disease. Remarkably, even moderate adherence to the MIND diet has been shown to lower the risk of Alzheimer’s by approximately 35%, with high adherence potentially cutting that risk by up to 50%.
This scoring system could also effectively assess the risk of heart disease, cancer, and diabetes. My only reservation lies with awarding a point for a daily glass of wine; existing evidence does not substantiate this. Instead, I would recommend allocating a point for abstaining from alcohol. Regardless, if your score exceeds 9, it likely indicates a reasonably healthy diet. However, it’s essential to note that a holistic lifestyle approach is what truly matters. Relying solely on adding olive oil to salads or swapping yogurt for ice cream is misguided.
