The link between vitamins in the diet and quality of life

The link between vitamins in the diet and quality of lifeThe diet’s content of vitamin C, vitamin B6, vitamin B12, folic acid, and other vitamins has a positive impact on our mental and physical health and well-being Lack of vitamins may even remedy depression and chronic pain, according to a Japanese study of seniors. The number of seniors worldwide is increasing with more and more people being affected by physical and mental disease. Therefore, scientists want to take a closer look at the diet and its influence on quality of life measured by different accounts.

By year 2050, the number of people in the world aged 60 years or older is expected to have increased to 2.1 billion. According to WHO, “Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity”. It is therefore also necessary to assess quality of life from a mental, physical, and social point of view. With that in mind, the new Japanese study focuses on these three parameters and assesses them using different rating scales.
It is already known that quality of life is affected by a number of different environmental and lifestyle factors. Earlier studies have even shown that healthy eating habits have a huge impact on our physical and mental health. Nonetheless, the available information concerning specific vitamins’ impact on quality of life is limited, which is why the Japanese scientists took a closer look at this in their new study.

Study material and methods

The scientists used data from an earlier Japanese study (the Shika study). The analyses included more than 3,000 people aged 40-99 years with an even number of men and women. The scientists used a health survey named SF-36 (The Short Form-36 Health Survey) that is not limited to specific diseases and evaluates quality of life using a physical score, a mental score, and a social score.
The participants were asked to fill in questionnaires about their eating habits for an entire month. The questions looked specifically at their consumption of 58 different foods, including rice, fish, and meat plus beverages with or without alcohol.
Based on the answers, the researchers were able to calculate the individual participant’s intake of energy (calories), protein, carbohydrate, fats, and the following vitamins: Pure vitamin A (retinol), beta-carotene (a precursor of vitamin A), vitamin D, vitamin E, vitamin K, vitamin B1, vitamin B2, vitamin B3 (niacin), vitamin B6, vitamin B12, folic acid (vitamin B9), pantothenic acid, and vitamin C. The scientists only looked at dietary vitamins, not vitamins from supplements. Participants with too low daily calorie intake (less than 600 kcal/day) or too high calorie intake (over 4,000 kcal/day) were excluded from the analysis, as this could skew the results.

Vitamins and quality of life

It turned out that women with a low score in terms of mental quality of life consumed significantly lower quantities of niacin and vitamin B6 compared to women that scored higher in terms of mental quality of life. There was generally a positive relation between female intake of niacin, vitamin B6, folic acid, and vitamin C and the score on the mental scale. Men with a lower score in terms of mental quality of life consumed less vitamin B2. Other than that, however, there was no clear relation between men’s vitamin intake and their score on the mental scale.

Vitamins and physical quality of life

Women with a low score in terms of physical quality of life consumed significantly less vitamin A, vitamin K, vitamin B2, niacin, vitamin B6, vitamin B12, folic acid, pantothenic acid, and vitamin C compared to women with a high score. There was a strong correlation between women’s intake of vitamins and their physical and mental health. The new study is published in Nutrients, where the researchers also refer to other studies of diet and its influence on health.

The diet and its impact on mental and physical health

Depression is one of the most common and widespread diseases, affecting 322 million people worldwide. It is primarily women who are affected by depression and the number is increasing every single year. The scientists behind the Japanese study refer to other studies showing that depression is more prevalent among middle-aged women with low vitamin B intake. Depression is also more common among middle-aged and older women who consume less beta-carotene and vitamin C. Lack of vitamins can generally result in impaired mental quality of life because of things like depression, failing memory, and cognitive impairment.

The diet and its role in overweight, depression, and chronic pain

There is even a link between depression, overweight, and chronic pain. Many people who are overweight tend to consume unhealthy diets with too many empty calories and therefore lack nutrients and suffer from other nutritional imbalances. It has been observed that overweight Japanese women with a tendency towards depression have lower intake of the different B vitamins.


Nobuhiko Narukawa et al. Relationship between Vitamin Intake and Health-Related Quality of Life in a Japanese Population: A Cross-Sectional Analysis of The Shika Study. Nutrients 2021