- According to a new study, a deficiency in folic acid (vitamin B9), which is important in early childhood, can cause problems for people in middle age.
- The study found that reducing folic acid intake allows older mice to more easily switch between day and night metabolism, or from fat burning to carbohydrate burning.
- Although folic acid is associated with healthy blood, the older mice in the study showed no signs of developing anemia.
- The study represents an early step in research in this area, but finds similar results in yeast cells and worms.
According to a new study, while taking folic acid is considered healthy for everyone – and clearly benefits young people – it can lead to metabolic problems in older people.
The study in mice by AgriLife Research at Texas A&M University found that lower levels of folic acid, the naturally occurring form of vitamin B9, facilitated the transition from sleep metabolism to wake metabolism.
When mice and humans sleep, their metabolism focuses on burning body fat. During waking hours, it’s all about burning carbohydrates to generate the energy needed for daily activities.
The current study supports the results of an earlier study by the researchers in which they used methotrexate to limit folate consumption in yeast cells and also reduce folate uptake in the worm. C.elegansBoth yeast and worms lived longer than the control group that consumed typical amounts of folic acid.
In the current study, a cohort of middle-aged mice (52 weeks) was placed on either a standard diet or a low-folate diet.
The researchers found no evidence of anemia in the folate-deficient group, meaning they somehow still had enough red blood cells. They also did not observe reduced viability or lower body weight. The males in this group actually weighed more than their counterparts on a normal diet.
The effects of folate reduction later in life on life expectancy were not explicitly examined in the study because all mice were euthanized after 120 weeks. However, males on both diets and females appeared to have similar life expectancies.
The study was published in Life Sciences Alliance.
The study’s lead author, Michael Polymenis, PharmD, PhD, who teaches biochemistry and biophysics at Texas A&M, said Medical news today“As we age, we cannot quickly switch from one type of metabolism (e.g. burning fat while sleeping) to another (e.g. burning carbohydrates when we wake up). Rapid transitions are necessary to meet our body’s needs when needed.”
Michelle Routhenstein, MS, RD, CDCES, preventive cardiology dietitian at EntirelyNourished.com, who was not involved in the study, explained, “During the day, when we are active, the body primarily uses carbohydrates for energy, with higher insulin levels facilitating glucose uptake. At night, insulin sensitivity decreases, causing the metabolism to switch to using stored fat because the body’s energy needs are lower and growth hormone levels increase.”
“As we age,” says Polymenis, “our bodies become less able to adapt their energy supply to changing needs, which can impact our overall health and energy levels.”
Routhenstein emphasized that folic acid is “essential for various body functions, including DNA synthesis, cell repair and red blood cell production.”
“They are especially important during periods of rapid growth,” she noted, “such as during pregnancy and infancy, and support cell function and division in adults while helping to prevent anemia.”
“Folic acid is also very important for cardiovascular health, especially as we age. Folic acid lowers homocysteine levels – a risk factor for heart disease – supports the repair of vascular cells and may have anti-inflammatory effects,” Routhenstein said.
Some foods that contain folic acid include:
- asparagus
- Avocado
- Brussels sprouts
- Chickpeas
- Leafy vegetables
- Lettuce
- Liver (avoid during pregnancy)
- Peas
- spinach
One interesting question the study raises is how the mice deprived of folic acid still managed to have enough red blood cells to avoid anemia. “That’s an excellent question,” Polymenis said.
“It’s important to remember that even though these mice were not receiving dietary folate, they still had enough folate to maintain red blood cell function. Their folate levels were 30-40% of those of control mice that received dietary folate,” he said.
The question remains: What is the source of these red blood cells?
“It almost certainly comes from the bacteria in their gut,” Polymenis said. “So diet is not our only source of folate.”
“Our study also suggests that maintaining a healthy gut microbiome is crucial and may be enough to ensure adequate levels of vitamins, such as folate, and prevent associated health problems.”
—Michael Polymenis, PharmD, PhD
It is well known that folic acid is important for a healthy diet, at least for younger people. It is also worth noting that Polymenis’ team has so far worked with yeast, worms and mice, but has not proven its hypothesis in humans. For this reason, he advises caution.
“We advocate not making changes in humans. While we believe our study is promising and needs to be followed up, it is a relatively small study in mice. At this stage, it underscores the need for further research before we advocate changes in older adults,” Polymenis said.
Currently, Routhenstein says, “folate remains important for overall health, including cardiovascular well-being, so it is crucial to focus on a diet rich in folate-containing foods.”
“It is recommended to consult a registered dietitian to stay up to date on new nutritional research and continue to follow established dietary guidelines,” she added.
Polymenis suggested a possible method for implementing folate reduction in the elderly if the results of his research are confirmed in humans.
Some foods now contain nutritional additives—milk is fortified with vitamin D, for example, and cereals and breads are added with folic acid. He envisioned a time when a folate-reducing additive might be a means for middle-aged and older people who don’t need folate to easily reduce their folate intake.
