Wheat causes arthritis.
Before you say "What the hell is he saying now?", let me connect the dots on how this ubiquitous dietary ingredient accelerates the path to arthritis in its many forms.
1) Wheat causes glycation--Glycation is glucose-modification of proteins in the body that occurs when blood glucose exceeds 100 mg/dl. Cartilage cells are especially susceptible to glycation. The cartilage cells you had at age 18 are the very same cartilage cells you have at age 60, since they lack the ability to reproduce and repair themselves. Proteins in cartilage are highly susceptible to glycation, which makes them stiff and brittle. Stiff, brittle cartilage loses its soft, elastic, lubricating function. Damaged cartilage cells don't regenerate nor produce more protective proteins. This allows destruction of cartilage tissue, inflammation, and, eventually, bone-on-bone arthritis.
Because wheat, even whole wheat, sends blood sugar higher than almost all other foods, from table sugar to Snickers bars, glycation occurs after each and every slice of toast, every whole wheat bagel, every pita wrap.
2) Wheat is acidifying--Humans are meant to consume a diet that is net alkaline. While hunter-gatherers who consume meat along with plentiful vegetables and fruits live a net alkaline diet (urine pH 7 to 9), modern humans who consume insufficient vegetables and too much grain (of which more than 90% is usually wheat) shift the body towards net acid (urine pH 5 to 7). Wheat is The Great Disrupter, upsetting the normal pH balance that causes loss of calcium from bones, resulting in decalcification, weakness, arthritis and osteoporotic fractures.
3) Wheat causes visceral fat--The extravagant glucose-insulin surges triggered by wheat leads to accumulation of visceral fat: wheat belly.
Visceral fat not only releases inflammatory mediators like tumor necrosis factor and various interleukins, but is also itself inflamed. The inflammatory hotbed of the wheat belly leads to inflammation of joint tissues. This is why overweight and obese wheat-consuming people have more arthritis than would be explained by the burden of excess weight: inflammation makes it worse. Conversely, weight loss leads to greater relief from arthritis pain and inflammation than would be explained by just lightening the physical load.
We need a name for this wheat effect. How about "bagel bones"?