What do people who live a long life have in common? First, it helps to have good genes. Beyond that there are several recurring themes and three lifestyle pillars that are found in cultures with many nonagenarians and centenarians. The first two are exercise and diet. The third pillar is social connections. The trifecta of social networks, food and exercise come together to form a healthy community. In medicine every intervention (medication, surgery, procedure, or therapy) is thought of in terms of its risk and benefit. It is felt that exercise, a good diet and social connectivity each have a vast benefit in promoting a healthy lifestyle with little or no risk. Is this true? Can one over exercise? Is a healthy diet really that healthy? Can social connections be detrimental?
“Exercise is king. Nutrition is queen. Put them together and you have a kingdom”, said Jack LaLanne, a noted celebrity fitness expert who passed away at the age of 96. Exercise is the key to living a long healthy life and you don’t have to be a world-class athlete to obtain the benefits. Moderate walking every day will increase lifespan by one and a half years while more vigorous walking will increase it by three years. The recommended amount of exercise to reduce the risk of heart disease and lower the death rate is 150 minutes of moderate exercise per week or 75 minutes of vigorous exercise per week. The second pillar is diet. Plant based protein diets and the Mediterranean diet have become the standards for heart healthy eating. The Mediterranean diet emphasizes olive oil, fresh vegetables, nuts, whole grains over refined grains, fish and plant-based protein over red meat, herbs and spices to flavor food over salt, and fresh fruit for dessert instead of refined sweets. The Mediterranean diet can lower the risk for heart attack, stroke and cardiac death by a substantial 30%, a risk reduction similar to taking medications such as statins to lower cholesterol.
Following a good exercise regimen and eating a healthy diet are largely individual interventions. A healthy lifestyle can be accomplished on one’s own, but a healthy community requires a social network. There are places in the world where people live much longer than average. In these places, residents walk before and after dinner, eat healthy meals together and dine with friends and family. This is shown in the picture above, a town in Italy where everyone is out, walking, talking, eating, socializing, and connecting with each other. Much of the social support is in the home, where multiple generations live together. On the other hand, social isolation increases the risk for heart disease and stroke by 30%. People who are socially isolated tend to engage in negative health behaviors such as smoking, drinking excess alcohol and not exercising or eating correctly. Social networks are a major factor in improving longevity. Having supportive friends and family can make life easier by providing emotional support, providing help when needed, reducing stress and providing the impetus to go out and walk and connect with others. The depth and quality of the social connections matter as well. Having one friend bests being alone, but having a larger network is better still. In some cultures, people brag about how much money they have. In cultures with longevity, they brag about how many friends they have. People with adequate social relationships tend to live nearly four years longer than those without support. All cardiac rehab programs combine these three elements as well. Cardiac rehab programs are structured as cohorts; similar patients with similar cardiac problems exercise together, eat together and support each other. In effect, a good cardiac rehab program is a type of healthy community. There does not seem to be a down side to developing a strong social network. Or is there?
Unfortunately, all three pillars have a down side. For example, it is possible to over exercise and that risk is associated with some harm. The highest risk of cardiac death is in the sedentary individual. Exercising will decrease the risk of dying from heart disease. The more exercise, the lower the risk of cardiac death, up to a point. As one exercises more, the risk of dying continues to go down and eventually plateaus. However, in athletes who exercise ten times or more than the recommended amount (for example training for and running multiple marathons in a year), the risk of cardiac death actually stops going down and starts trending upward. In other words, the extreme athlete may be at higher risk than the person who walks 150 minutes per week. So, exercise has its down side, but how about the vaunted Mediterranean diet? Recently, it lost some of its luster as the major study which proved the Mediterranean diet’s worth was found to have flaws. The diet is still good, but the evidence is now much weaker. What is the downside to a wide social network and lots of friends? Coronavirus.
The novel coronavirus has caused a global pandemic. The virus is transmitted via respiratory droplets; an infected person passes on the virus by coughing, sneezing, talking or breathing. This method of transmission worsens with close personal contact, thus the need for social isolation to contain it. The fatality rate for coronavirus is age-specific. The death rate is low for children under 9 years of age ( < 1 percent) and goes up with advancing age. The rate accelerates after age 60 (the death rate at 60 to 65 is about 5%) and is highest in those over 80 with rate nearing 15 percent. Multigenerational households are especially hard hit; younger adults come home with no or mild symptoms, but pass the virus to their elderly family members who live with them. This may be one reason why lower income areas of cities are vulnerable. Even though these areas have a high proportion of people with medical problems (such as high blood pressure, obesity and heart disease) putting them at risk for infection, they also have multiple people living in each household and several generations cohabiting. Paradoxically, countries such as Italy and Spain, home to many healthy communities with presumably low rates of high blood pressure and heart disease, have been harshly affected by the coronavirus. There are many reasons for this, including a country’s response to the pandemic. However, there are intrinsic characteristics of these countries which may be contributing. For example, Italy has the second oldest population in the world with 23 percent over age 65 (Spain has 19 percent over age 65, the US 16 percent). In addition, these countries have dense kinship networks and are known for the support that elderly parents receive from their adult children. They have extended households with more than one adult couple living in the same house. In Italy 34 percent of people over 65 had an adult child in the house. In Spain it is 38 percent. For comparison, in northern European countries the rate is 2 percent. These Southern European countries, with their family centered cultures, are normally areas with many healthy communities and good overall health but now their living arrangements and social closeness potentiate the spread of the virus.
In 1931 Kurt Godel published his Incompleteness Theorems, transforming mathematical logic. The theorems state (as interpreted by a cardiologist and not a mathematician) that every formal system is either incomplete or inconsistent. This is important because the theorems show that it is impossible to create a set of rules that explain everything in math. What does a mathematical theory have to do with a pandemic and public health? The coronaviruses’ effect on healthy communities proves Godel’s theorem; nothing is perfect.