Diet, sleep patterns, and blood pressure in young individuals

In a recent study published in Hypertension Research, a group of researchers examined the relationship between dietary and sleep rhythms and blood pressure (BP) levels in children aged 6-15 from Chongqing and Sichuan provinces and identified optimal rhythm interventions to prevent Cardiovascular diseases (CVD) onset potentially.

Study: The impact of dietary and sleep rhythms on blood pressure in children and adolescents: a cross-sectional study. Image Credit: OleksandraNaumenko/Shutterstock.com

Background 

Contemporary lifestyles frequently exhibit irregular eating patterns and inadequate sleep. These habits might heighten the risk for chronic ailments like obesity, hypertension, and diabetes. People now eat beyond a 15-hour window daily, deviating from the traditional three meals a day seen in the 1970s.

Coupled with prevalent poor sleep, especially among the young, these irregularities pose a risk for hypertension by disrupting the body’s circadian rhythm.

Further research is needed because while multiple studies highlight the effects of irregular dietary patterns and poor sleep on adult blood pressure, there is limited understanding of these impacts on children and adolescents, making it crucial to establish guidelines for this younger population.

About the study 

The present study, conducted in 2021 and 2022, used a three-stage stratified cluster sampling to select two provinces in Chongqing and Sichuan, one county per province and two avenues per county.

This led to the inclusion of four primary and two middle schools and targeted children aged 6-15 years residing in these avenues for over six months.

Participants filled out questionnaires on demographics, diet, socio-economic status, and family health history. From the initial 6,450 children, 5,608 were analyzed for dietary rhythm and 5,320 for sleep rhythm after data adjustments. 

Dietary and sleep rhythms were determined through self-reported questionnaires detailing meal timings and sleep durations. Discrepancies between weekday and weekend rhythms were also calculated. BP was precisely measured on three distinct occasions by trained nurses from the Children’s Hospital of Chongqing Medical University using a specific sphygmomanometer model to diagnose hypertension.

The study also looked at potential covariates or confounding variables collected via questionnaires. These encompassed demographic information, prenatal factors like birth weight, anthropometric data, lifestyle habits, and socio-economic indicators. Height and weight were precisely measured using a specific medical device, and body mass index (BMI) was calculated.

Analytical tools, including the general linear (GLM) and logistic regression models, were employed to dissect the relationships between dietary and sleep rhythms and BP levels. In addition, subgroup analyses by gender were conducted.

Two criteria helped determine optimal meal and sleep times. First, a model in SAS identified relationships between meals/sleep times and BP levels, indicating optimal times for lowered BP. Second, school timings for primary and middle school students were also factored in. SAS 9.4 software handled all data analysis, with a significance set at 0.05 in two-sided tests.

Study results 

The study assessed data from 5,608 children aged 6–15 years, with 47.3% being girls and 52.7% boys, and the average age of the participants was 10.48 years. Information such as height, weight, BMI, birth weight, and socio-economic factors were recorded, and girls were found to have a lower mean arterial pressure.

Over half of the participants, about 53.21%, were in their puberty stages, and a significant 69.86% were exposed to passive smoking. A minority, 10.97%, came from families with a single, separated, divorced, or widowed parent.

The study recorded that 39.93% of fathers and 20.61% of mothers were obese, while the prevalence of hypertension was 2.89% for mothers and 5.94% for fathers. After multiple readings on different days, 140 children, including 91 boys and 49 girls, showed elevated blood pressure.

Dietary and sleep patterns varied with age for instance, children aged 6-7 years had a mean feeding window of 11.69 hours on weekdays, which increased with age. The study also found that older participants, aged 13-15, had earlier breakfasts and later dinners than their younger counterparts.

Sleep durations also varied: children aged 6–7 slept approximately 9.62 hours on weekdays, 8-12-year-olds slept about 9.18 hours, and 13-15-year-olds had an average sleep duration of 7.89 hours.

Weekends saw a pattern shift, with later mealtimes, wake-up times, and longer sleep durations than weekdays. Notably, the sleep and dietary rhythms of teenagers aged 13 to 15 were more varied than younger age groups.

The relationship between dietary and sleep patterns and blood pressure levels was also investigated. Results indicated that a longer weekday feeding window was associated with higher systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP).

Breakfast timings had an inverse relationship with these blood pressure metrics, while dinner timings had a positive relationship with DBP and MAP.

One notable finding was that having breakfast later reduced the chances of high blood pressure by about 30%. Among the key findings, waking up later on weekdays was a protective factor against elevated blood pressure.

This protective effect was more pronounced in boys, while a later bedtime was a protective factor for girls. Variations in wake-up times had a different impact, as it lowered the likelihood of high blood pressure in girls but increased it for boys.

An optimal dietary and sleep rhythm was defined based on meal timings and durations. Children with ideal dietary patterns had lower SBP, DBP, and MAP than those who did not adhere to these patterns. Specifically, male participants with optimal nutritional and sleep patterns had a reduced chance of hypertension.

In conclusion, the study sheds light on the crucial connection between dietary and sleep rhythms and their effects on blood pressure in children and adults.