A diet designed decades ago to reduce hypertension also appears to significantly lower uric acid, the causative agent of gout, according to US researchers.
They found the effect on uric acid levels of a diet rich in fruits, vegetables, low-fat dairy and reduced in fats and saturated fats nearly matched the impact of current gout medicines.
“A dietary approach to prevent gout should be considered first line therapy”
They said their findings, published in the journal Arthritis and Rheumatology, could offer an effective, safe and sustainable dietary approach to lower uric acid and possibly prevent gout flare-ups in those with mild to moderate disease.
The researchers, from Johns Hopkins University in Baltimore, said that while dietary excesses had long been associated with gout, its precise causes remain “somewhat of an enigma”.
They noted that it had also been unclear exactly what type of diet might help lower the elevated levels of uric acid linked to gout symptoms – such as severe inflammation and sharp pain in joints.
The researchers, led by Dr Stephen Juraschek, used data from the DASH (Dietary Approaches to Stop Hypertension) clinical trial, an often-cited study whose results were first published in 1997.
It showed that the DASH diet – which emphasizes reduced salt, whole grains, fruits, vegetables, low-fat dairy products and reduced intake of red meats, sweets and saturated fats – had a marked positive improvement on blood pressure and cholesterol.
In the original trial, 412 participants ate either the DASH diet or a typical American diet for three months.
In the new study, the researchers used the data to see whether the DASH diet affected uric acid blood concentrations. They found it led to a modest 0.35 milligrams per deciliter decrease overall.
However, they also found that the higher participants’ baseline uric acid levels, the more dramatic the decrease.
For example, in those with the highest baseline uric acid levels, more than 7 milligrams per decilitre, the decrease was as high as 1.3 milligrams per deciliter.
- Gout patients ‘need better care’, says arthritis charity
- Guidance aims to improve gout treatment
- Warning over shortage of rheumatology nurses
Dr Juraschek said that, taking into context of what was known about levels of uric acid and gout flare-up risk, the study had produced “a large reduction in uric acid”.
He said: “When you get as high as the reduction we believe occurred with the original DASH diet in this study, the effect starts being comparable with gout medications.”
Gout-treating medications, such as allopurinol, often reduce patients’ blood uric acid concentrations about 2 milligrams per deciliter.
The researchers cautioned that further research was needed to more clearly establish the link and to directly explore whether the DASH diet might reduce or prevent gout flare-ups.
However, they suggested the diet could offer patients a viable way to control uric acid concentrations through a diet already shown to have positive effects on blood pressure.
Study senior author Professor Edgar Miller said: “Results of this trial are good news to patients with high blood levels of uric acid or those at risk for gout.
“A dietary approach to prevent gout should be considered first line therapy,” he said. “This study suggests that standard dietary advice for uric acid reduction which is to reduce alcohol and protein intake, should now include advice to adopt the DASH diet.”