Poor Sleep Increases High Blood Pressure

A recent study found that older men who got less deep sleep have a higher risk of hypertension.  In the study, men with the lowest level of the deeper stages of slumber, known as slow-wave sleep, had an 80% higher chance of developing high blood pressure than men with the highest level of slow-wave sleep.

For the study, researchers evaluated 784 men with an average age 75.  In 2003-05, the men did not have high blood pressure. When they returned for a follow up in 2007-09, the investigators found that 243 men had developed high blood pressure.  The researchers divided the men into four groups, from those with the lowest amount of slow-wave sleep to the highest.  In this study, the men averaged 11.2% of slow-wave sleep but those in the lowest of the four groups averaged only 4% of restorative slow-wave sleep and these individuals developed hypertension at significantly higher rates than those who got more restorative sleep. 

As persons age, the amount of slow-wave sleep they get typically declines.  Among children as much as much as 40% of their sleep is comprised of slow-wave sleep while among middle-aged adults typically only about one-fourth of their sleep is slow wave.   When one goes to sleep blood pressure normally falls, especially while in deep sleep, but exactly why lack of deep sleep influences overall blood pressure is not known.    

“The new research adds to information about the importance of sleep,” said Dr. Alberto Ramos, co-director of the University of Miami Sleep Disorders Center.  “Experts agree that not enough sleep, over time, can boost the risk of high blood pressure.  The new study goes further by suggesting that the quality of your sleep, specifically the amount of deep sleep, plays as important a role in developing high blood pressure as the actual amount of time you sleep." 

What to do:  Adults can take measures to try to increase slow-wave sleep by decreasing the number of times they wake up in the night.  Thus, setting up your sleep environment to not wake you up and timing your fluid intake so that you do not need to wake up to go to the bathroom can help.  Also, having a regular sleep pattern appears to be associated with better quality sleep.  Additionally, it is important to prevent and/or be treated for underlying sleep disorders that can wake you up -- such as sleep apnea.  Maintaining a healthy weight is the best way to prevent developing sleep apnea.

Sources:  Aug. 29, 2011, Hypertension, online & http://www.nlm.nih.gov/medlineplus/news/fullstory_115892.html.

DRINKING JUICE INCREASES WEIGHT GAIN, HAVE FRESH FRUIT INSTEAD

Do not drink your calories is good advice if you are trying to watch your weight, even if it is 100% fruit juice that you are drinking.  In a recent study, that appeared in the journal Obesity, researchers gave 34 young men and women 20% of their usual caloric intake (400-550 calories) per day in the form of either solid fruits and vegetables or fruit juice.   Half of the participants were overweight or obese and half were at a healthy weight.  The solid food treatment consisted of 6-8 servings per day made up of 10% vegetables, 35% fresh fruit, and 55% dried fruit.  The juice treatment consisted of all fruit juices. 

After eight weeks on the added solid fruits and vegetable, the participants who were healthy weight had not gained any weight.  The researchers hypothesized that they cut back on their other intake when they were eating additional fruits and vegetables.  However the healthy weight persons on the added juice diet gained 3 pounds.  The weight outcomes for the overweight and obese participants were even worse.  They gained 4 pounds after 8 weeks on the added fruits and vegetables diet and gained 5 pounds while on the added fruit juice diet.   Why did the overweight persons gain weight on both diets?  It may have been because these persons continued to eat their regular diet in addition to the fruits and vegetables that researchers gave them.

What to do:  Eat whole fruits and vegetables instead of drinking the juice.  Research has repeatedly found that foods that we drink do not fill us up so we usually consume these calories in addition, not instead, of the solid foods that we eat.  Even though many juices come from 100% fruit sources, they are still high in calories and natural fruit sugars.  Additionally, much of the fruit given in this study was in the form of dried fruit which is more calorie dense than fresh fruits.   Small amounts of dried fruit can also add up quickly in calories.  While diets high in fruits and vegetables are associated with better weight outcomes it is still important to remember than when you are increasing your fruit and vegetable intake, opt for these foods instead of other higher calorie foods that you eat, not in addition to your regular diet.

For Heart Health, Some Exercise Is Better than None. And More Is Even Better…

In a new analysis of existing studies, researchers at the Harvard School of Public Health found convincing evidence that people who walk or jog for just a couple of hours each week are at significantly lower risk of heart disease than those who don't exercise.  And, for those that exercise rigorously or for longer periods, there are even more heart health benefits.  The researchers collected data from nine past studies that asked participants how frequently they exercised, and for how long each time, and followed them to see who was diagnosed with heart disease over anywhere from a few years to a couple decades.

United States guidelines from 2008 recommend 150 minutes of moderate exercise (such as brisk walking) each week, or 30 minutes five days per week, as a minimum for health benefit. Twice that, the guidelines say, adds additional benefit.  The authors of the new study, led by Jacob Sattelmair, wanted to test the benefit of exercise on heart disease in relation to these federal guidelines.

This study corroborates the long known fact that regular aerobic activity helps reduce blood pressure, improves blood flow in the heart, and reduces heart health risks overall.  In this study researchers found that the heart health benefits of exercise abound and that the more people exercise the lower their chances of heart problems.  They found that people who exercised according to the minimum guidelines (equivalent to burning about 550 calories per week through exercise) had a 14% lower risk of heart disease than those who didn't exercise at all.  For those who met the higher guideline standard (about 1100 calories per week), that improved to a 20% lower risk.  Even people who only got half as much exercise as the minimum guidelines also had some heart protection compared to non-exercisers.

The study did not look at the difference between moderate and more vigorous exercise, but researchers said that people who work out intensely get the same or greater benefit from less time than "moderate" exercisers.

While the findings show that more is generally better, "If you're doing nothing, you don't have to start walking an hour a day to achieve benefit…If you're totally sedentary...as little as 10 to 15 minutes of brisk walking a day was associated with a reduction in risk of heart disease" Sattelmair explained. "Everyone can benefit from movement and physical activity and exercise."

What to do:  Get regular physical activity.  The benefits go beyond heart health to include nearly every aspect of physical and mental health.  People who exercise regularly experience improved mental well being as well as improved sleep.  When starting exercise people who are at risk of heart disease and not used to working out should consult with their physician and, if appropriate, gradually build up their routines in intensity and duration.   Being overweight and having diabetes or high cholesterol adds to heart risks.

HIGH SODIUM, LOW POTASSIUM DIET LINKED TO INCREASED RISK OF DEATH & HEART ATTACK

According to a new study by the Centers for Disease Control and Prevention, Emory University, and Harvard University, Americans who eat a diet high in sodium and low in potassium have a 50% increased risk of death from any cause, and about twice the risk of death from heart attack.  The study analyzed data from the National Health and Nutrition Examination Survey which draws on data from a large, diverse sample of Americans.

  

"The study's findings are particularly troubling because U.S. adults consume an average of 3,300 milligrams of sodium per day, more than twice the current recommended limit for most Americans," said investigator Dr. Elena Kuklina. 

The 2010 Dietary Guidelines for Americans (DGA) recommends limiting intake of sodium (primarily consumed as salt) to 1,500 mg (less than 2/3 of a teaspoon of salt) per day for people 51 and older, African Americans, and those who have high blood pressure, diabetes, or chronic kidney disease.   For persons not in these higher risk groups they advise limiting sodium to less than 2,300 mg of sodium (about 1 teaspoon of salt) per day.  The DGA also advises people consume more potassium rich fruits and vegetables with the target potassium intake at 4,700 mg for most adults. 

What to do:  Aim to limit sodium intake and increase your intake of potassium.  Nearly 80% of people's sodium intake comes from packaged and restaurant foods.  For example, cheese, processed meats, breads, soups, fast foods, and pastries tend to have more sodium.   In contrast, processed foods tend to be low in potassium.  Potassium rich foods include whole grains, most fruits and vegetables, and dairy products.   Especially good sources of potassium include leafy greens, such as spinach and collards, brussel sprouts, mushrooms, grapes, blackberries, bananas, carrots, potatoes and citrus fruits.  Adults can improve their blood pressure by choosing foods like fresh or frozen fruits and vegetables, and unprocessed or minimally processed fish, meat or poultry, low-fat milk or plain yogurt, asking for foods with no or low salt at restaurants, and evaluating the nutrition labels of foods that list both sodium and potassium content.

AMERICANS ARE EATING MORE OFTEN AND CONSUMING MORE CALORIES FROM SNACKS

Two recent studies indicate that much of Americans' increased calorie consumption stems from eating more frequently.   University of North Carolina researchers examined surveys of daily eating habits from the last 30 years and found that the average number of daily meals and snacks consumed by U.S. adults rose from 3.8 in 1977 to 4.8 in 2006.   Researchers also found that while the size of meal portions has stabilized in recent years, total calories consumed over the course of the day continues to rise.  By 2006, Americans were consuming 570 more calories per day than they did in the late 1970s and most of those extra calories came from extra snacks rather than larger meals.

A chief culprit behind the calorie gain: Americans now consume 220 more calories daily from sugar-sweetened soft drinks than they did in the 1960s, the study found.  Study author Kiyah Duffey said that large portion sizes drove the rise in calories during the early part of the study period but that more recently increased intake stems more from the frequency of intake rather than the size of portions.  “A proliferation of food availability and a decline in regular mealtimes may be fueling the pattern…People aren't sitting down to three meals anymore," she said.

Another study of Americans' snacking behaviors conducted at Purdue University found that snacking now accounts for about 25% of the calories consumed by Americans each day.  Moreover, on average, about half of those calories come from beverages.   Researcher Richard D. Mattes also found that between 2006 and 2008, the amount of time Americans spent eating solid food snacks increased from an average of 15 minutes per day to 30 minutes per day.  Similarly, over that time period, the time Americans spent drinking snack beverages rose from 45 minutes per day to 85 minutes per day.  In contrast, during that same period, the time spent eating primary meals (breakfast, lunch and dinner) remained roughly constant at around 70 minutes.

What to do:  While small frequent meals appear to be helpful for many persons when they are trying to reduce their total calorie intake, these studies point out that eating often can also be a source of a lot of additional calories and add up to more intake in the end.   If you do eat more frequently, you need to reduce your intake at your breakfast, lunch, and dinner.  Also, be strategic about what you snack on.  Snack foods typically are not very healthy options, and if you are opting for snacks over meals, you may be selecting sugary or high fat options.  Because these are very tasty and not very filling, we are more likely to overeat these than traditional meal components such as protein sources or vegetables.   Also, do not drink your calories.  Beverages can have a lot of calories but are not filling so people can easily overdo it with sugary drinks.  It is also important to be careful about mindless eating.  Spending long periods snacking means we are spending more time eating while doing other things such as watching TV, using the Internet, and driving.  Research consistently shows that when we do not focus on our food we eat more and feel less satisfied.   It is important that while you're eating, only be eating. So, step away from the email and turn off the TV while you're eating.

Adapted from Institute of Food Technologists, news release, June 21, 2011 & Reuters Health, 2011.