Some animal sources increase gout while plant sources may not
Gout is thought of as an inflammatory arthritis. It occurs intermittently, affecting the joints, most commonly the big toe. The symptoms are acute (sudden onset) and include extremely painful, red, swollen and tender joints. Uric acid (or urate) levels are directly related to the risk of gout attacks. As uric acid levels increase, there is a greater chance of urate crystal deposits in the joints.
This disease affects more than three million people in the U.S. (Arthritis Res Ther. 2006;8:Suppl 1:S2). Men between 30 and 50 years old are at much higher risk for their first attack. For women, most gout attacks occur after menopause.
There are a number of potential causes of gout, as well as ways to prevent and treat it. Though heredity plays a role, these risk factors are modifiable. The best way to prevent and treat gout is with medication and lifestyle modifications.
I thought we might look at gout using a case study. I recently had a patient who had started a nutrient-dense, plant-based diet. Within two weeks she had a gout episode. Initially, it was thought that her change in diet with increased plant purines might have been an exacerbating factor. Purines are substances that raise the level of uric acid. However, as we will see, not all purines equally raise uric acid levels.
Animal versus plant proteins
In a recent case-crossover (epidemiologic forward-looking) study, it was shown that purines from animal sources increase the level of purines far more than those from plant sources (Ann Rheum Dis. online May 30, 2012). The risk of a gout incident was increased approximately 241 percent in the group consuming the highest amount of animal products, whereas the risk of gout was still increased for those consuming plant-rich purine substances, but by substantially less: 39 percent.
The authors believe that decreasing the use of purine-rich foods, especially from animal sources, may decrease the risk of incident and recurrent episodes of gout. Plant-rich diets are the preferred method of consuming proteins for patients who suffer gout attacks, especially since nuts and beans are excellent sources of protein and many other nutrients.
In another study, meats — including red meat, pork and lamb — increased the risk of gout, as did seafood (NEJM 2004;350:1093-1103). However, purine-rich plant sources did not increase risk of gout. Low-fat dairy actually decreased the risk of gout by 21 percent. The study was a large observational study involving 49,150 men over a duration of 12 years. Therefore, it is unlikely that the patient switching to a nutrient-dense, plant-rich diet increased her risk of gout.
Diuretics (water pills)
My patient was on a diuretic called hydrochlorothiazide for hypertension (high blood pressure). There are several medications thought to increase the risk of gout, including diuretics and chronic use of low-dose aspirin. In the ARIC study, patients who used diuretics to control blood pressure were at a 48 percent greater risk of developing gout than nonusers (Arthritis Rheum. 2012 Jan;64(1):121-9). In fact, nonusers had a 36 percent decreased risk of developing gout. This study involved 5,789 participants and had a fairly long duration of nine years. The longer the patient is treated with a diuretic, the higher the probability they will experience gout. It is likely that my patient’s diuretic contributed to her gout episode.
There are a number of medical conditions that may impact the risk of gout. These include uncontrolled high blood pressure, diabetes and high cholesterol (www.mayoclinic.com). My patient’s high blood pressure was under control, but she also had diabetes and high cholesterol. These disorders may have contributed.
Obesity, like smoking, seems to have its impact on almost every disease. In the CLUE II study, obesity was shown to not only increase the risk of gout but also accelerate the age of onset (Arthritis Care Res (Hoboken). 2011 Aug;63(8):1108-14). Those who were obese experienced gout three years earlier than those who were not. Even more striking is the fact that those who were obese in early adulthood had an 11-year earlier onset of gout. The study’s duration was 18 years. My patient was obese and had started to lose some weight before the gout occurred.
Vitamin C may reduce gout risk. In the Physicians Follow-up Study, a 500 mg daily dose of vitamin C decreased levels of uric acid in the blood (J Rheumatol. 2008 Sep;35(9):1853-8).
The key to success with gout lies with prevention. Patients who do get gout writhe in pain. Luckily, there are modifications that significantly reduce the risks. They involve very modest changes, such as not using diuretics in patients with a history of gout, losing weight for obese patients and substituting more plant-rich foods for meats and seafood. Although the cause of gout may be apparent to you, always check with your doctor before changing your medications or making significant lifestyle modifications as we have learned from this case study of my patient.
Dr. Dunaief is a speaker, author and local lifestyle medicine physician focusing on the integration of medicine, nutrition, fitness and stress management. For further information, go to the website www.medicalcompassmd.com and/or consult your personal physician.