Eating Lots of Acidic Foods Linked to Worse, Longer Depression in MS
Worse depression scores over 5 years tied to high dietary acid intake
Eating a lot of acidic foods like meat, eggs, cheese, and grains — and fewer alkaline ones, such as fruits, vegetables, and milk — is significantly associated with worse depression scores over five years among people with multiple sclerosis (MS), a study found.
“The level of depression at the 10-year review was determined by both the baseline [starting] dietary acid scores and baseline-5-year changes in dietary acid scores,” the researchers wrote.
While the findings need to be confirmed in further studies, they suggest a need to adjust diet in MS patients to include more alkaline foods and reduce the intake of acid-inducing foods, the team noted.
“If these associations are indeed causal, then interventions that reduce the dietary acid load longer term may be effective in lowering depression levels in people with MS,” they wrote.
The study, “Long-term dietary acid load is associated with depression in multiple sclerosis, but less evidence was found with fatigue and anxiety,” was published in the journal Multiple Sclerosis and Related Disorders.
Eating acidic foods linked to depression
A diet rich in acid-forming foods — that is, foods from animal sources and cereal grains — and low in alkaline-forming foods, such as fruits and vegetables, can result in too much acid being produced in the body. This happens because the so-called dietary acid-base load gets out of balance.
A high dietary acid load has been linked to worse mental health in the general population, and in people with diabetes and breast cancer. Researchers questioned whether this also might hold true for people with MS.
To find out, a team of researchers in Australia tracked a group of individuals for 10 years after their first episode of neurological symptoms suggestive of MS, known as clinically isolated syndrome.
Their aim was to determine whether higher dietary acid load scores would be linked to worse symptoms of MS, specifically depression, fatigue, and anxiety, in these individuals over the long run.
Their cohort included 190 people who took part in a multicenter, case-control study, called the Ausimmune Study — short for Australian Multi-centre Study of Environment and Immune Function. Only those who received a diagnosis of MS over the 10-year study period were included in the analyses.
At study entry, and then after five and 10 years, participants were asked to complete a food questionnaire to determine their dietary intake over the previous 12 months.
Based on their answers, researchers derived two measurements — potential renal acid load (PRAL) and net endogenous acid production (NEAP) scores — to accurately reflect the intake of acidic and alkaline foods. For both measures, higher scores indicate a greater consumption of acidic foods, and lower scores reflects more alkaline food intake.
The Hospital Anxiety and Depression Scale (HADS) was used to assess depression and anxiety, while the Fatigue Severity Scale (FSS) was used to measure fatigue.
Results showed no association between dietary intake in the past year and current depression, anxiety, or fatigue. But a higher consumption of acidic foods was significantly associated with higher depression scores after five and 10 years.
The researchers divided patients into four groups (quartiles), from the highest PRAL and NEAP scores to the lowest. Those who in the highest PRAL group experienced an increase in depression scores by 1.4 points after five years. In contrast, those in the lower quartile saw their depression improve by 1.6 points.
Similar findings were observed at the 10-year time point.
As for anxiety and fatigue, some links were observed in the same direction, “but were much weaker and less consistent,” the researchers wrote.
While there is no evidence that a special diet will help with the symptoms of MS, there are recommendations for people with the disease to eat a healthy diet.
With the new findings in hand, the researchers suggest that “a diet focusing on an increased consumption of alkaline-inducing food and a reduction of acid-inducing foods could be tested in a randomised controlled trial in people with MS with depression.”