**1. Introduction**

According to the World Health Organization, population aging is a global phenomenon rapidly evolving worldwide. By 2030, the number of people aged 60 and over in the world is projected to grow from 901 million to 1.4 billion, or 56%. It is expected that by 2050, the global population of people over 65 will amount to about 2.1 billion people, more than double compared to 2015. In addition, it is estimated that by 2050, the over eighty-year-olds throughout the world will be around 434 million, or more than three times compared to 2015, when they reached 125 million. The rapid aging of the population can be observed above all in emerging economy countries. In fact, over the next 15 years, the elderly population will grow more rapidly in Latin America and the Caribbean with an expected increase of 71%, followed by Asia (66%), Africa (64%), Oceania (47%), North America (41%), and Europe (23%) [1]. This means that while European countries have had more than 150 years to adjust to an increase of up to 20% in the proportion of the population over 65, countries like Brazil, China, and India will have less than 20 years to adapt to a similar one. The population as of 1 January 2018 in the European Union (EU) was estimated to be 512.4 million. People over 65 years old amounted to 19.7%, an increase of 2.6% compared to 10 years earlier. The percentage of people aged over 80 is expected to at least double by 2100 to 14.6% of the entire EU population [2].

It is also true that many elderly people maintain good autonomy and live life with a good level of well-being. These subjects, despite the presence of one or more diseases, however, do not have serious illnesses or physical disabilities; they have good mental health, preserved cognitive functions, maintain a good level of physical activity levels and

**Citation:** Capurso, C. Whole-Grain Intake in the Mediterranean Diet and a Low Protein to Carbohydrates Ratio Can Help to Reduce Mortality from Cardiovascular Disease, Slow Down the Progression of Aging, and to Improve Lifespan: A Review. *Nutrients* **2021**, *13*, 2540. https:// doi.org/10.3390/nu13082540

Academic Editor: Camillo Ricordi

Received: 16 June 2021 Accepted: 23 July 2021 Published: 25 July 2021

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in some cases, are engaged in social and productive activities [3,4]. All these conditions define successful aging.

It is known that a healthy life in middle age predisposes successful success. This includes a healthy diet with adequate caloric intake to the state of health and physical activity, smoking cessation, and taking moderate amounts of alcohol, preferably with meals. The traditional Mediterranean diet (MD) is characterized by a high intake of foods of plant origin (fruit, vegetables, whole-meal bread, beans, nuts, and seeds) and fresh fruit; extra virgin olive oil is the main dietary source of fat.

Traditional MD has long been recognized as a highly healthy dietary pattern. High adherence to traditional MD leads to a significant reduction in mortality and a reduced risk of developing cardiovascular disease and cancer as well as a reduced risk of developing chronic disease and disability in later life. The main source of complex carbohydrates is made up of cereals and their derivatives (bread, pasta, rice); these provide 55–60% of the total caloric intake and are placed at the bottom of the food pyramid [5–15].

Another health diet model other than MD is the traditional Okinawan diet [16]. This is also characterized by a low overall caloric intake, high consumption of vegetables, high consumption of legumes (mainly soybeans), moderate consumption of fish, especially in coastal areas, in any case, by the low consumption of meat, especially lean pork. Characteristic of traditional Okinawa is also a low consumption of dairy products, a high intake of mono- and polyunsaturated fats, with a low omega 6:3 ratio, the consumption of low glycemic index carbohydrates with a high intake of fiber, and a moderate consumption of alcohol. Figure 1 compares the composition of the MD and the Okinawan diets.

**Figure 1.** Mediterranean diet and Okinawan diet pyramids.

The purpose of our review was to analyze both cohort and case-control studies that investigated, on one hand, the effects of cereals, of whole grains (WG), and derivatives in the diet, on the other, the effects of a diet with low protein–carbohydrate ratio on aging progression, mortality, and lifespan.
