Feeling tired all the time has become a common part of modern life. Many people juggle busy work schedules, family responsibilities, and daily stress while trying to keep up with endless demands.
As a result, fatigue is often blamed on a lack of sleep or not taking enough breaks. However, researchers are beginning to find that another factor may be contributing to low energy levels: poor nutrition.
A new study from Osaka Metropolitan University in Japan suggests that deficiencies in two important vitamins, vitamin B12 and folate, may be linked to fatigue and low motivation, even among otherwise healthy people.
The research, published in the journal Nutrients, provides new evidence that what we eat every day may have a greater influence on our energy levels than many people realize.
Vitamin B12 and folate, also known as vitamin B9, play important roles in the body. They help produce healthy red blood cells, support brain function, and contribute to many processes that keep the body working properly.
When levels of these vitamins become too low, various health problems can develop. Scientists have long known that deficiencies can cause anemia and neurological problems, but their connection to everyday fatigue has been less clear.
The research team, led by Professor Hiroaki Kanouchi, focused on a substance in the blood called homocysteine. Homocysteine is often used as a marker of nutritional status because its levels tend to rise when people do not get enough folate or vitamin B12.
High homocysteine levels have previously been linked to conditions such as heart disease, dementia, and bone fractures.
To explore whether homocysteine might also be linked to fatigue, the researchers studied approximately 600 healthy adults in Japan. Blood samples were collected to measure levels of homocysteine, folate, and vitamin B12. Participants also completed questionnaires designed to assess physical fatigue, mental fatigue, and motivation.
The first results confirmed what scientists expected. Participants with higher homocysteine levels generally had lower levels of vitamin B12 and folate. This pattern was seen in both men and women.
The researchers then took a closer look at how homocysteine levels related to feelings of fatigue. They carefully adjusted for other factors that could affect energy levels, including age, sleep habits, workload, and dietary patterns. This allowed them to better isolate the relationship between nutritional status and fatigue.
The findings revealed an interesting difference between men and women. Among men, higher homocysteine levels were associated with greater physical fatigue. Men with elevated levels were more likely to report feeling physically tired and lacking energy.
Among women, the relationship appeared slightly different. Higher homocysteine levels were linked to lower motivation rather than physical fatigue. Women with elevated levels were more likely to report feeling less motivated to engage in activities and daily tasks.
According to the researchers, this may be the first study to demonstrate a connection between vitamin B12, folate, and fatigue-related symptoms in healthy individuals. The findings suggest that nutritional deficiencies may influence how energetic and motivated people feel, even before obvious illness develops.
The study also highlights the importance of maintaining a balanced diet. Foods rich in folate include leafy green vegetables, beans, lentils, citrus fruits, and fortified grains. Vitamin B12 is mainly found in animal products such as meat, fish, eggs, and dairy foods. People who eat highly restrictive diets may be at greater risk of deficiencies.
One strength of the study is that it involved a relatively large group of healthy participants and considered many other factors that influence fatigue.
However, the research cannot prove that low vitamin levels directly caused fatigue because it only measured associations. Future studies will be needed to determine whether improving vitamin intake can directly reduce tiredness and improve motivation.
Even with these limitations, the findings offer an important reminder that fatigue is not always simply the result of being busy. Sleep, stress, exercise, and nutrition all contribute to how people feel. This study suggests that paying attention to vitamin B12 and folate intake may be another useful step for people struggling with low energy.
Overall, the research provides valuable evidence that a healthy, balanced diet may support not only physical health but also everyday energy and motivation. While more research is needed, the study suggests that nutritional status deserves greater attention when people experience ongoing fatigue.
Source: Osaka Metropolitan University.
