Intelligence in youth and health behaviours in middle age

Abstract

ObjectiveWe investigated the association between intelligence in youth and a range of health-related behaviours in middle age.MethodParticipants were the 5347 men and women who responded to the National Longitudinal Survey of Youth 1979 (NLSY-79) 2012 survey. IQ was recorded with the Armed Forces Qualification Test (AFQT) when participants were aged 15 to 23 years of age. Self-reports on exercise (moderate activity, vigorous activity, and strength training), dietary, smoking, drinking, and oral health behaviours were recorded when participants were in middle age (mean age = 51.7 years). A series of regression analyses tested for an association between IQ in youth and the different health related behaviours in middle age, while adjusting for childhood socio-economic status (SES) and adult SES.ResultsHigher IQ in youth was significantly associated with the following behaviours that are beneficial to health: being more likely to be able to do moderate cardiovascular activity (Odds Ratio, 95% CI) (1.72, 1.35 to 2.20, p < .001) and strength training (1.61, 1.37 to 1.90, p < .001); being less likely to have had a sugary drink in the previous week (0.75, 0.71 to 0.80, p < .001); a lower likelihood of drinking alcohol heavily (0.67, 0.61 to 0.74, p < .001); being less likely to smoke (0.60, 0.56 to 0.65, p < .001); being more likely to floss (1.47, 1.35 to 1.59, p < .001); and being more likely to say they “often” read the nutritional information (1.20, 1.09 to 1.31, p < .001) and ingredients (1.24, 1.12 to 1.36, p < .001) on food packaging compared to always reading them. Higher IQ was also linked with dietary behaviours that may or may not be linked with poorer health outcomes (i.e. being more likely to have skipped a meal (1.10, 1.03 to 1.17, p = .005) and snacked between meals (1.37, 1.26 to 1.50, p < .001) in the previous week). An inverted u-shaped association was also found between IQ and the number of meals skipped per week. Higher IQ was also linked with behaviours that are known to be linked with poorer health (i.e. a higher likelihood of drinking alcohol compared to being abstinent from drinking alcohol (1.58, 1.47 to 1.69, p < .001)). A u-shaped association was found between IQ and the amount of alcohol consumed per week and an inverted u-shaped association was found between IQ and the number of cigarettes smoked a day. Across all outcomes, adjusting for childhood SES tended to attenuate the estimated effect size only slightly. Adjusting for adult SES led to more marked attenuation but statistical significance was maintained in most cases.ConclusionIn the present study, a higher IQ in adolescence was associated with a number of healthier behaviours in middle age. In contrast to these results, a few associations were also identified between higher intelligence and behaviours that may or may not be linked with poor health (i.e. skipping meals and snacking between meals) and with behaviours that are known to be linked with poor health (i.e. drinking alcohol and the number of cigarettes smoked). To explore mechan...

An epigenetic predictor of death captures multi-modal measures of brain health

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Childhood IQ predicts age‐38 oral disease experience and service‐use

“…For example, an investigation of the association of IQ measured in adolescence with self‐reported health by age 40 in a large US cohort study found that higher cognitive scores predicted better general and mental health, along with lower odds of having a number of conditions, including self‐reported “severe tooth or gum trouble” . Other work with that same cohort has highlighted an important role for intelligence in health behaviours known to be important for oral health, with, for example, better cognitive performance at ages 15‐23 years predicting higher rates of dental floss use and lower rates of smoking and consumption of sugary drinks in middle age . Data from a British cohort study showed that more intelligent children grow up to exercise more and eat more healthily as adults .…”

“…10 Other work with that same cohort has highlighted an important role for intelligence in health behaviours known to be important for oral health, with, for example, better cognitive performance at ages 15-23 years predicting higher rates of dental floss use and lower rates of smoking and consumption of sugary drinks in middle age. 11 Data from a British cohort study showed that more intelligent children grow up to exercise more and eat more healthily as adults. 12 Given the key role of sugars exposure in dental caries occurrence, 13 these findings suggest that intelligence might be a key determinant of oral health through life.…”

“…Cohort families represent the full range of socioeconomic status in the general population of New Zealand's South Island and are primarily of white European ancestry. Follow-up assessments were conducted with informed consent at 5,7,9,11,13,15,18,21,26,32, and most recently at 38 years of age, when 95.4% of the 1007 living study members took part.…”

Genetic Contributions To Health Literacy

“…Individuals with higher cognitive function tend to participant more in health promoting behaviours. [11][12][13][14] Vascular risk factors, including diabetes and hypertension, have been associated with poorer cognitive function and greater cognitive decline. [15][16][17][18] Cognitive function, measured early in life, has been found to predict later life physical functioning and health status, 19 psychological distress, 20 psychiatric illness, [21][22][23][24][25] dementia, 26 and death.…”