According to a recent study in Brain, Behavior, and Immunity, there appears to be a connection. The study was based on data from a two-day nationwide survey conducted on 50,000 Swedish males 18-20 years of age in 1969-70 before they went into military service. Blood samples were taken at that time to test for a general marker of inflammation known as ESR (erythrocyte sedimentation rate). Although ESR is a very crude marker of inflammation, it was one of only a few available in the late ‘60s.
Then the blood samples were taken again 35 years later. In their statistical analyses, the authors took into account a wide number of other variables, which may have influenced the results (socio-economic status, height, weight, blood pressure, smoking, etc.) and concluded that as inflammation (as measured by ESR) increased, there was a decline in IQ. In addition, a higher level of inflammation at age 18–20 was significantly associated with an increased risk of mortality during a 35-year follow-up (1). The results of the study show that even at an early age low-grade inflammation can significantly impact intelligence and premature death.
The underlying cause of chronic disease (and therefore early mortality) is increased cellular inflammation. Likewise a drop in intelligence is usually an indication of an increase in dementia at an earlier age. Dementia is also driven by cellular inflammation in the brain. The most sensitive marker of cellular inflammation is the AA/EPA ratio in the blood. Therefore it is not surprising that five years ago it was demonstrated the higher the AA/EPA ratio in the blood of elderly age-matched individuals, the greater their degree of their cognitive deficits (2).
The anti-inflammatory Zone Diet was developed to reduce cellular inflammation and has been clinically validated to do exactly that (3,4). So if you have a wish to live a longer and better life, then life-long control of cellular inflammation through the anti inflammatory diet makes perfect sense. That’s why the anti inflammatory diet is not a diet but a way of life.
- Karlsson H, Ahlborg B, Dalman C, and Hemmingsson T. “Association between erythrocyte sedimentation rate and IQ in Swedish males aged 18–20.” Brain, Behavior, and Immunity 24: 868–873 (2010).
- Conquer JA, Tierney MC, Zecevic J, Bettger WJ, and Fisher RH. “Fatty acid analysis of blood plasma of patients with Alzheimer's disease, other types of dementia, and cognitive impairment.” Lipids 35:1305-1312 (2005).
- Pereira MA, Swain J, Goldfine AB, Rifai N, and Ludwig DS. “Effects of a low glycemic-load diet on resting energy expenditure and heart disease risk factors during weight loss.” JAMA 292: 2482-2490 (2004).
- Johnston CS, Tjonn SL, Swan PD, White A, Hutchins H, and Sears B. “Ketogenic low-carbohydrate diets have no metabolic advantage over nonketogenic low-carbohydrate diets.” Am J Clin Nutr 83: 1055-1061 (2006).