• There is ongoing research on how food relates to mental well-being and mental health conditions such as depression.
• An area of study is how foods impact aspects like happiness and life satisfaction.
• A recent study suggests that certain foods, like fish and vegetables, may be linked to positive psychological well-being.

Does what we eat contribute to positive mental well-being? One studyTrusted Source published in the British Journal of Health PsychologyTrusted Source sought to understand the connection. Rather than focusing on how foods help with negative psychological states, this research chose to focus on how food affects positive mental well-being.

Researchers found that higher intake of fruits, vegetables, and fish was linked to three domains of well-being and that polyunsaturated fatty acid intake was linked to two domains of well-being.

After model adjustment, fruit and vegetable intake remained linked to eudemonic well-being, and fish intake remained linked to happiness. The findings suggest that food may affect positive psychological well-being.

This research focused on how diet affects positive mental well-being. The authors note that this area includes three domains. The first is eudemonic well-being, which has to do with a sense of purpose as well as aspects like having positive relationships. The second is affective well-being, which involves positive emotions like happiness. The third is evaluative well-being, which is overall life satisfaction. These factors of positive well-being were measured via three assessment scales.

Researchers used data from the English Longitudinal Study of Ageing and looked at the relationship between “diet and positive well-being among middle-aged and older adults in England.” They included 3,103 participants in their final sample.

The specific foods they included were fruits and vegetables, fish, and polyunsaturated fatty acids (PUFAs). The researchers noted that PUFAs are “a type of fat that includes omega-3 and omega-6 fatty acids, essential for cell, nerve, and brain functions.”

The researchers accounted for covariates, including age, wealth, social isolation, and depressive symptoms. They used a total of five models in their statistical analysis, with each model adding in more covariates. Of note, the authors of this study sought to adjust for depressive symptoms in their analysis, something they believe has been lacking in previous research.

A majority of participants were not socially isolated, did not live alone, had low scores for depression, and denied having a long-standing illness that limited activities. About 30% were in the highest category for wealth.

On average, participants had two portions of fruits and vegetables each day, and over half of the participants reported not eating fish.

Researchers identified several intercorrelations between factors. For example, they identified that wealth and education levels had a positive correlation with “most key variables.”

When it came to well-being, there was some variation in how different foods impacted different areas of well-being. Higher fruit and vegetable intake was associated with greater eudemonic well-being, and this held true in all the models. In contrast, PUFAs only had this association until the model that considered depressive symptoms, and fish only had this association “up to model 2.”

When it came to happiness, greater fish intake was associated with higher levels of happiness in all models, while the other foods only had this link after adjusting for depressive symptoms. Higher fruit and vegetable intake was linked to higher life satisfaction until researchers accounted for long-standing illness. They did not find a significant association between PUFAs and life satisfaction, and for fish, there was only an association in the first model.

Researchers believe the univariate analysis suggests that fruits and vegetables, PUFAs, and fish were linked to greater levels of well-being, as well as lower symptoms of depression.

Overall, the results suggest that different foods have varying effects on positive psychological well-being. It also highlights that fruit and vegetable intake “appears to have the strongest link to positive well-being.”

Study author Pepper Theeraoat, MSc (UCL), and a PhD candidate, noted the following about the study’s findings to Medical News Today:

“As seen from the results in our study, different types of food are differentially associated with well-being. For instance, even after accounting for other factors, higher fruit and vegetable intake was linked to higher eudemonic well-being, while higher fish intake was linked to greater happiness.”

This study does have limitations. First, it did rely on participant reporting, which can lead to reporting bias and recall bias. Additionally, a lot of the components were subjective, which might minimize actual results. Data on diet only came from two 24-hour recall questionnaires.

Most of the participants were white, which can limit generalizability to other groups, and since it focused on middle-aged and older adults, it’s unclear how the results would differ for younger people. More research may also need to focus more specifically on older adults.

Yoshua Quinones, MD, a board-certified Internist with Medical Offices of Manhattan and contributor to https://www.labfinder.com/, who was not involved in the study, noted that “People don’t always remember food intake correctly unless they’re actually writing everything down in a food diary. Finally, this study was done in older adults in England, which may not apply to different cultures or younger people.”

Since participants had a fairly low level of PUFAs, it’s possible that this affected the researchers’ ability to identify the link between PUFAs and well-being. More research may be needed in this area. Since less than half of the participants reported eating fish, more research into the relationship between fish and positive psychological well-being may also be helpful.

Can food lead to more positive well-being?

Since the research was cross-sectional, it’s not clear whether higher intake of certain foods boosts well-being or whether greater well-being leads to people making healthier and more varied food choices, but the results may suggest that food choices affect positive psychological well-being. However, the study does not determine cause.

As noted by the authors in this study, there are many factors that affect a person’s well-being and diet. Therefore, it’s possible that researchers did not account for factors that could have affected the observed relationships.

More research is required to study the full effect of these food choices on positive psychological well-being, as well as to conduct appropriate long-term follow-up.

Theeraoat noted what future research could include:

“Intervention studies and clinical trials, where diet is manipulated (e.g., increased fruits and vegetables, fish, or polyunsaturated fats) and changes in well-being are tracked over time, would be particularly valuable. Longitudinal studies are needed to clarify the direction of the relationship between diet and well-being…Lastly, cross-cultural research would help examine whether the links between diet and psychological well-being hold across different countries and cultures.”

The research may indicate a need for increased education in this area. Mir Ali, MD, a board certified general surgeon, bariatric surgeon, and medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, CA, who was also not involved in the study, noted the following to Medical News Today:

“I see this as another reason to educate people at an early age on the importance of a healthy diet. Lack of understanding of the impact of diet on all aspects of health greatly contributes to the rise of many health issues as we age. Early education and adjustment to a healthier diet can have a huge impact on health, especially for older adults.”

“Since diet is modifiable, increasing the intake of healthy foods such as fruits, vegetables, fish, and healthy fats may play a promotive and a preventive role in supporting psychological well-being.”
— Pepper Theeraoat, MSc

Theeraoat noted that “It is also worth looking at dietary improvements alongside standard treatments, as lifestyle factors like diet should not be overlooked. ‘You are what you eat’ does hold: what we consume can be helpful or harmful to our physical and mental health.”

Share this article