The excessive uric acid level in the blood (hyperuricemia) is risk factors for gout attacks, which are generally defined as uric acid levels> 6.8 mg/dl (404 µmol / L).

Various factors can affect blood uric acid levels, namely excessive production, for example, due to high purine diets, as well as due to lack of excretion, for example, due to consumption of diuretics, kidney failure, and genetic defects.

A low purine diet is considered to reduce blood uric acid levels, so it is used to prevent and treat gout. Gout arthritis results from deposits of uric acid crystals in the joints that trigger an inflammatory response.

GOUT Arthritis and Diet
A Patient is getting pain of gout.
Image Source: https://www.thesun.co.uk


Association between Diet and Gout

Several food factors have been linked to the incidence of gout through observational studies. There is scientific evidence that consuming alcohol, sweetened drinks, meat, seafood, and high-fructose foods has a positive association with gout.

Meanwhile, consumption of dairy products, coffee, and micronutrients has been associated with lower incidences of gout and gout flare. However, many of these studies have a high risk of bias, such as recall bias, and cannot determine the causative relationship between diet and gout.


Purine Intake and Gout Risk

A study by Zhang et al., Involving 633 study subjects, tried to evaluate the relationship between purine intake and the risk of gout recurrence. The study found that a high intake of purines would increase the recurrence of gout by five times. They concluded that avoiding or reducing high purine food intake, especially from animal sources, can reduce the risk of gout attacks.

The Purine Content in Food
Nuts, soy products, and average cereals contain ≤50 mg / 100 g of purine. Dried soybeans contain more purines than other nuts, which is 172.5 mg / 100 g. Tofu, soy milk, and other processed soy products contain ≤50 mg / 100 g of purine.

Meanwhile, eggs and most dairy products contain almost no purine or ≤13 mg / 100 g. Most mushrooms also contain low levels of purines, ranging from 6.9 to 98.5 mg / 100 g. Bananas and strawberries also have low purine levels of 2-3 mg / 100g.

About 70% of vegetables have a purine level of ≤50 mg / 100 g. Vegetables with moderate to high purine content are parsley and spinach. On the other hand, 60% of meat has a purine content of ≥100 mg / 100g. Chicken liver has a very high purine content, which is 312.2 mg / 100 g. Meanwhile, beef liver contains 219.8 mg / 100 g of purine, and pork liver contains 284.8 mg / 100 g of purine. The purine content in processed meat ranges from 45.5-138.3 mg / 100 g, with the highest prosciutto and salami content.

Just like meat, most fish contain ≥100 mg / 100 g of purine. Some seafood with high purine content are sardines, bonito, gnomefish, and small shrimp (krill).



Diet Program to Prevent Gout

A cross-sectional study of 2076 healthy subjects found that dairy products, calcium, lactose, and sweetened drinks significantly increased uric acid levels. However, consumption of high purine vegetables and fructose intake with measured calories were found to be unrelated to plasma uric acid levels. Conclusion This study concludes that limiting the consumption of high purine vegetables does not effectively reduce uric acid levels.

A systematic review states that consumption of high-purine foods sourced from animals and seafood is crucial in increasing uric acid levels. Meanwhile, foods high in purines from vegetables do not cause significantly similar effects. This study also reports that vitamin C consumption can increase uric acid excretion to be used as a supplement for gout management. It also said that consuming foods rich in vitamin C, oils from plants such as olive oil, sunflower oil, and soy could reduce hyperuricemia and gout risk.



DASH Diet for Gout

A prospective cohort study shows that dietary patterns based on Dietary Approaches to Stop Hypertension (DASH) are associated with significantly lower gout risk. In contrast, Western dietary patterns (high intake of red meat, processed meat, sweetened foods, french fries, and refined grains) are associated with 1.42-fold increased gout risk. This study concluded that the DASH diet had a good effect in reducing uric acid levels in hyperuricemia patients to prevent gout.

The DASH diet is a combination of low sodium (<300 mg / day), high potassium (4700 mg / day), magnesium (> 420 mg / day), calcium (> 1000 mg / day), and fiber (25- 30 g / day), and low in saturated fatty acids and cholesterol (<200 mg / day). In this diet, it is recommended to use fresh, natural, and not through industrial processes.

The DASH diet emphasizes more fruit-vegetable intake to achieve 30 g of fiber a day for a 2100 calorie meal plan per day, low in dairy products, and low in saturated fat. The recommended daily calories in the DASH diet come from 55% carbohydrates, 18% protein, 27% fat, and not more than 6% saturated fat.



Conclusion
Existing observational studies show that consumption of animal-based foods, dairy products, and drinks containing sweeteners can increase hyperuricemia and gout risk. Meanwhile, plant-based diets, including high purine plants, do not increase uric acid levels and gout risk. A recent study shows that the DASH dietary pattern, which is commonly used for hypertensive patients, also has benefits in preventing the incidence of gout.