Eating a diet rich in plants, fish, and olive oil tends to be associated with improved mental health and emotional resilience in older adults. Recent research published in journals BMJ Open Our findings suggest that a Mediterranean-style diet provides a protective buffer for psychological health, even during times of widespread social stress, such as the COVID-19 pandemic. These findings provide evidence that nutrition plays an important role in helping older adults maintain a positive outlook on life.
The Mediterranean diet is a dietary method based on the traditional diet of countries bordering the Mediterranean Sea. This dietary pattern focuses on plant-based foods such as vegetables, fruits, beans, nuts, and whole grains, and relies on fish and extra virgin olive oil as the main fat sources. In general, limit your intake of red meat, dairy products, and processed sweets. Extensive research has linked this particular food combination to improved physical health, including a lower risk of heart disease and clinical depression.
Scientists know that proper nutrition can help prevent negative mental conditions such as depression, but less attention has been paid to how food influences positive psychological well-being. Positive happiness is not simply the absence of sadness or anxiety. This includes an active, positive state of mind, such as a sense of control, independence, purpose, and overall enjoyment of life. This kind of positive psychological state can lead to longer survival and less disability later in life.
The research team, consisting of Andrew Steptoe and Alana Jo Shand from University College London, and Camille Lasalle from the Barcelona Institute for Global Health, wanted to see whether eating habits influence these positive emotions. They specifically targeted older adults to see if a Mediterranean diet could support an active and meaningful mindset during the aging process. They also wanted to test how this relationship holds up when people face sudden and severe emotional challenges.
To investigate this, researchers analyzed data from the British Longitudinal Study of Aging. A longitudinal study is a research design in which the same variables are observed repeatedly over a long period of time. This special project will track the health, financial situation and social lives of older people in the UK. For this analysis, the team included 3,296 men and women over the age of 50, with an average age of approximately 68 years.
From 2018 to 2019, these participants completed a detailed online dietary assessment. To measure eating habits, participants used an internet-based tool that asked them to recall everything they ate and drank over two separate 24-hour periods. The survey included images of portion sizes to help participants report their dietary intake as accurately as possible. This tool tracked over 200 different foods and beverages and calculated accurate nutritional intake.
The researchers then scored these food responses using an index known as the Relative Mediterranean Diet Index. This index assesses how closely a person’s dietary habits align with the traditional Mediterranean diet on a scale of 0 to 18. A higher score indicates greater adherence to the dietary habit. A high score means the person eats more fish, legumes, and plants, consumes moderate amounts of alcohol, and eats little meat or dairy products.
To measure mental health, participants completed a specific questionnaire designed to assess positive psychological health. The survey asks individuals to rate statements about their sense of independence, energy level, and whether they feel their life has meaning. Scientists collected these happiness scores during the first period of 2018-2019. They also collected happiness scores again from a returning group of 3,023 original participants in June and July 2020, during the early months of the COVID-19 pandemic.
Initial analysis of 2018-2019 data reveals a positive association between food choices and mental outlook. Participants who scored higher on the Mediterranean Diet Index also reported significantly higher levels of positive psychological well-being. This relationship held true even after the authors accounted for other factors that influence happiness. The researchers adjusted the statistical model to account for household income, education level, physical activity, smoking status, and pre-existing physical conditions.
Interestingly, this association remained significant even when the researchers took into account whether the participants had symptoms of depression. This detail suggests that positive happiness and depression are separate experiences. Although you may not be clinically depressed, you may still lack a sense of purpose or joy. This data provides evidence that the Mediterranean diet not only prevents negative emotions, but also specifically supports the presence of positive emotions.
Tracking data from summer 2020 allowed scientists to see how diet interacts with major stressful events. As expected, the restrictive lockdown measures, social isolation, and general fear surrounding the early COVID-19 pandemic led to lower levels of positive psychological well-being across the study group. People generally reported feeling less control and enjoyment in their daily lives.
However, people who adhered to a Mediterranean diet before the pandemic experienced less decline in health. Even after taking into account whether the participants had actually contracted the coronavirus, the Meals on Wheels association remained viable. Data suggests that this way of eating acts as an emotional buffer. It appears to help older adults maintain a sense of purpose and joy even in the face of significant social disruption and stress.
Although these findings are useful, there are some limitations that should be kept in mind. Because this study was observational rather than a controlled experiment, the authors cannot claim that the Mediterranean diet directly causes improvements in mental health. People who already feel happier and more purposeful are more likely to simply be more motivated to make healthy food choices. This type of bidirectional relationship is common in nutrition.
The study also relied on an online nutritional survey, which may have excluded older adults who were less familiar with computers and the Internet. In fact, the researchers noted that participants who completed the dietary survey tended to be wealthier, better educated, and generally healthier than those who skipped the survey. This means that the study group may not be fully representative of the UK’s aging population as a whole.
Additionally, relying on self-reported memories of what people ate over just two days may not fully reflect their normal long-term habits. Additionally, the majority of the study group was from Caucasian backgrounds, so the findings may not fully apply to other races and ethnicities. Future studies will need to follow more diverse populations over longer periods of time to better understand this relationship.
Scientists also hope that future research will uncover the exact biological mechanisms linking food and mood. Current theory suggests that the high amounts of dietary fiber, omega-3 fatty acids, and polyphenols in the Mediterranean diet play a protective role. Omega-3 fatty acids are healthy fats found in fish that support brain health, and polyphenols are compounds found in plants that protect cells from damage. These nutrients may support better brain function and a more stable, positive mood by reducing inflammation and improving bacterial communities in the gastrointestinal tract.
The study, “Mediterranean diet adherence and mental health before and during the COVID-19 pandemic: A prospective analysis of the British Aging Longitudinal Study,” was authored by Andrew Steptoe, Alana Jo Shand and Camille Lassalle.
