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Flow of Empty Calories Into Children’s Food Supply Must Be Reduced

Too Little, Too Much Sleep in Early Pregnancy Linked to High Blood Pressure in the Third Trimester

Study: Women Who Get Dental Care Have Lower Risk of Heart Disease

Lifestyle Intervention for Overweight Patients With Diabetes Provides Long-term Benefits

Flow of Empty Calories Into Children’s Food Supply Must Be Reduced

With over 23 million children and adolescents in the United States overweight or obese, the risks for many chronic diseases continue to increase. An article in the October issue of the Journal of the American Dietetic Association examines the diets of American youth and finds some disturbing results.

According to the study’s authors, Jill Reedy, PhD, MPH, RD, and Susan M. Krebs-Smith, PhD, MPH, RD, both of the Division of Cancer Control and Population Sciences, National Cancer Institute, Bethesda, Maryland, obesity among children and adolescents is one of the most important public health problems in the country. Resolving it requires changes in diet and physical activity, in order to affect energy balance. This means a dietary reduction in energy from current consumption levels. The article identifies the major sources of overall energy and empty calories.

For 2- to 18-year-olds, the top sources of energy were grain desserts, pizza, and soda. Sugar-sweetened beverages (soda and fruit drinks combined) provided almost 10% of total calories consumed. Nearly 40% of total calories consumed by 2- to 18-year-olds were in the form of empty calories from solid fat and added sugars. Half of empty calories came from six foods: soda, fruit drinks, dairy desserts, grain desserts, pizza, and whole milk.

Researchers examined data from the National Health and Nutrition Examination Survey, a nationally representative survey with a complex multistage, stratified probability sample. Trained interviewers conducted in-person 24-hour dietary recalls with all eligible participants, using automated data collection systems that included multiple passes. Calories from solid fats and added sugars were calculated from the USDA MyPyramid Equivalents Database. Empty calories were defined as the sum of energy from solid fats and added sugars.

Children of different ages get their energy from different sources. For example, the top five sources of energy for 2- to 3-year-olds included whole milk, fruit juice, reduced-fat milk, and pasta and pasta dishes. Pasta and reduced-fat milk were also among the top five sources of energy for 4- to 8-year-olds. Top contributors of energy also varied by race/ethnicity. For example, major contributors for 2- to 18-year-old non-Hispanic blacks included fruit drinks and pasta and pasta dishes, while Mexican Americans' top sources included Mexican mixed dishes and whole milk. Non-Hispanic blacks and whites consumed more energy from sugar-sweetened beverages (combining soda and fruit drinks) than from milk (combining all milks), whereas Mexican Americans consumed more energy from milk than from sugar-sweetened beverages.

Too Little, Too Much Sleep in Early Pregnancy Linked to High Blood Pressure in the Third Trimester

A study in a recent issue of the journal Sleep found that getting too little or too much sleep in early pregnancy is associated with elevated blood pressure in the third trimester. The study suggests that improving prenatal sleep hygiene may provide important health benefits.

Results show that the mean systolic blood pressure in the third trimester was 114 mmHg in women with a normal self-reported nightly sleep duration of 9 hours in early pregnancy, 118.05 mmHg in women who reported sleeping 6 hours or fewer per night, and 118.90 mmHg in women with a nightly sleep duration of 10 hours or more in early pregnancy. After adjustments for potential confounders such as age, race, and prepregnancy body mass index, mean systolic blood pressure was 3.72 mmHg higher in short sleepers and 4.21 mmHg higher in long sleepers. Similar results were found for diastolic blood pressure.

The study, led by Michelle A. Williams, ScD, SM, MS, AB, professor of epidemiology in the School of Public Health at the University of Washington and codirector of the Center for Perinatal Studies at Swedish Medical Center in Seattle, Washington, also found an association between sleep duration and preeclampsia, a condition that involves pregnancy-induced hypertension along with excess protein in the urine. The risk of developing preeclampsia was almost 10 times higher (adjusted odds ratio = 9.52) in very short sleepers whose nightly sleep duration was less than 5 hours during early pregnancy. Overall, about 6.3% of participants were diagnosed with either preeclampsia or pregnancy-induced hypertension without proteinuria.

The study involved 1272 healthy, pregnant women who completed a structured interview at 14 weeks’ gestation, on average. Sleep duration in early pregnancy was evaluated by the question, “Since becoming pregnant, how many hours per night do you sleep?” Only about 20.5% of women reported a sleep duration of 9 hours per night, which was used as the “normal” reference category because prior research indicates that pregnant women tend to have longer sleep duration patterns. About 55.2% of women reported sleeping 7 to 8 hours per night, 13.7% slept 6 hours or fewer, and about 10.6% slept 10 hours or more.

After delivery, data on maternal blood pressures at routine prenatal care visits were abstracted from participants’ medical records, providing an average of 12 blood pressure values for each participant. Women with pre-gestational chronic hypertension were excluded from the study. Mean systolic blood pressures were 111.8 mmHg and 111.4 mmHg in the first and second trimesters and 114.1 mmHg in the third trimester.

According to the authors, a number of mechanisms by which habitual short sleep duration may lead to increased blood pressure have been proposed. Because blood pressure is known to dip by an average of 10% to 20% during sleep, short sleep durations may raise the average 24-hour blood pressure and heart rate. This may lead to structural changes that gradually raise the pressure equilibrium of the entire cardiovascular system. Sleep restriction also may produce abnormalities in the levels of hormones such as endothelin and vasopressin, which play an important role in the cardiovascular system. The authors suspect that the association between long sleep duration and elevated blood pressures may be related to unmeasured confounders such as obstructive sleep apnea, depression, or insulin resistance.

Study: Women Who Get Dental Care Have Lower Risk of Heart Disease

A new study led by a University of California, Berkeley, researcher could give women a little extra motivation to visit the dentist more regularly. The study suggests that women who get dental care reduce their risk of heart attacks, stroke, and other cardiovascular problems by at least one-third.

The analysis, which used data from nearly 7000 people aged 44 to 88 years enrolled in the Health and Retirement Study, did not find a similar benefit for men.

Published recently in the journal Health Economics, the study compared people who went to the dentist during the previous 2 years with those who did not. “Many studies have found associations between dental care and cardiovascular disease, but our study is the first to show that general dental care leads to fewer heart attacks, strokes, and other adverse cardiovascular outcomes in a causal way,” said study lead author Timothy Brown, assistant adjunct professor of health policy and management at UC Berkeley’s School of Public Health.

Data from the Health and Retirement Study had been collected every 2 years from 1996 to 2004. This longitudinal study followed the same individuals over time, and each biennial survey included questions on whether subjects had visited the dentist and whether they had experienced a heart attack, stroke, angina, or congestive heart failure during the previous 2 years. Deaths from heart attacks or strokes also were included in the analysis. The study took into account other risk factors, such as alcohol and tobacco use, high blood pressure, and body mass index.

The study authors suggest that for dental care to have a protective effect, it should occur early in the development of cardiovascular disease. The researchers did not have data on the type of procedures used during the dental visits, but they pointed to other studies that indicated three-fourths of older adult dental visits involved preventive services, such as cleaning and fluoride and sealant treatments.

Lifestyle Intervention for Overweight Patients With Diabetes Provides Long-term Benefits

An intensive lifestyle intervention appears to help individuals with type 2 diabetes lose weight and keep it off, along with improving fitness, control of blood glucose levels, and risk factors for cardiovascular disease, according to a report in the recent issue of Archives of Internal Medicine.

Improving blood glucose control and cardiovascular risk factors in patients with type 2 diabetes is critical in preventing long-term complications of the disease. Emphasis has been placed on screening and pharmacologic management of these parameters.

The Look AHEAD (Action for Health in Diabetes) Research Group conducted a multicenter randomized clinical trial comparing the effects of an intensive lifestyle intervention to diabetes support and education among 5145 overweight or obese individuals (average age, 58.7 years) with type 2 diabetes. Of these, 2570 were assigned to the lifestyle intervention, a combination of diet modification and physical activity designed to induce a 7% weight loss in the first year and maintain it in subsequent years. Participants were seen and contacted by phone at least monthly for 4 years. The 2575 individuals assigned to the diabetes support and education group were invited to three group sessions each year focusing on diet, physical activity, and social support.

On average, across the 4-year period, individuals in the lifestyle intervention group lost a significantly larger percentage of their weight than did those in the diabetes support group (6.2% vs 0.9%). They also experienced greater improvements in fitness, hemoglobin A1c level (a measure of blood glucose), blood pressure, and levels of high-density lipoprotein (HDL, or “good” cholesterol). Individuals in the diabetes support group, on the other hand, experienced greater reductions in low-density lipoprotein (LDL, or “bad”) cholesterol, owing to greater use of cholesterol-lowering medications in this group.

At the end of 4 years, the lifestyle intervention group maintained greater improvements in weight, fitness, hemoglobin A1c levels, systolic blood pressure, and HDL levels. Though the differences between the two groups were greatest initially and decreased over time, the differences between the groups averaged over the 4 years were significant and indicate that the lifestyle intervention group spent a considerable time at lower cardiovascular disease risk.