Brief Answer:
crystals of uric acid

Detailed Answer:
Hello,

gout is caused by the deposition of uric acid crystals to various parts of the body including the skin, the kidneys and the joints. Crystals in the joint cavity cause inflammation with redness, swelling, fever and pain. Crystals in the skin cause the formation of nodules with white matter. Crystal deposition in the renal tubules cause destruction of the tubules and may cause chronic kidney disease.

Alcohol (particularly beers) is one of the most important things to avoid. Purine-rich diet increases uric acid. Other things to be avoided include the following:
- internal organs like kidneys, heart, sweetbreads, liver, etc
- fish with high fat content like mackerel, trout, anchovies, etc
- seafood like shrimps, crab, caviar, mussels, etc
- saturated fat (red meat, fat poultry, high fat dairy products, etc)

Food to prefer:
- low fat dairy products
- eggs
- fruits (cherries and others) and vegetables
- pasta
- cereals
- vitamin C

The rest of the foods can be eaten in moderation.
Loosing weight (if you're obese) will help. Being adequately hydrated also helps.High purine vegetables like mushrooms, asparangus, etc do not seem to cause increased uric acid production and can be eaten. Complex carbohydrates are acceptable. Simple sugars are not.

A general rule is that a patient with frequent gout attacks should be more cautious but the rest should not be so stressed about it.

I hope you find my comments helpful!
Kind Regards!

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