5 Nutrition Findings You Need to Know
| March 22nd, 2017
Is your diet as healthy as you think? Here, in recognition of Nutrition Month, are five new nutrition findings you need to know.
The new Higher Fat DASH diet
Oh, go ahead and enjoy that whole milk yogurt, even if you’re following the highly recommended DASH diet that can lower blood pressure.
DASH has had a re-think regarding fat.
The original DASH, in addition to being high in fruits and vegetables, also recommended low fat dairy food.
But a new study published in the American Journal of Clinical Nutrition found that a higher fat DASH diet lowered blood pressure to the same extent as the DASH diet, and also reduced triglycerides but did not significantly raise LDL (“bad” cholesterol).
The study tested the effects of higher fat in the DASH diet, which was originally designed to include only low-fat and nonfat dairy foods.
Researchers tested whether substituting full-fat for low-fat dairy foods would affect the blood pressure benefit, as well as a the favourable lipid and lipoprotein profile of the DASH diet.
Compared to the DASH diet, the HF-DASH has more total and saturated fat and less carbohydrate, the latter achieved primarily by reducing fruit juices and other sugars.
The researchers used a randomized trial of healthy individuals who ate a control diet, a standard DASH diet, and a higher fat, lower carbohydrate modification of the DASH diet (HF-DASH) for 3 weeks each. The Control diet contained less fibre, fruits and vegetables and more red meat than either of the DASH diets.
Blood pressure was reduced similarly in the DASH and HF-DASH diet compared to the control diet. The HF-DASH diet also significantly reduced triglycerides and there was no significant difference in LDL cholesterol response between these diets.
The conclusion: the modified HF-DASH diet presents an effective alternative to the widely recommended DASH diet, with less stringent dietary fat constraints.
Sugar-sweetened drinks linked to increased visceral fat
Drinking orange juice every day at breakfast or another sugar-sweetened drink a day could increase the type of body fat that affects diabetes and heart disease.
That warning comes from the American Heart Association which published the new research in its journal Circulation.
The research using data from the famous Framingham Heart Study showed that among middle-aged adults, there was a direct correlation between greater sweetened beverage consumption and increased visceral fat.
Visceral fat or “deep” fat wraps around important internal organs such as the liver, pancreas and intestines. It affects how hormones function and is thought to play a larger role in insulin resistance — which may boost Type 2 diabetes and heart disease risk.
The researchers did not observe this association with diet soda.
“Our message to consumers,” says study author Dr. Caroline Fox, “is to be mindful of how much sugar-sweetened beverages they drink.” She characterizes the study as adding “another piece of evidence to the growing body of research suggesting sugar-sweetened beverages may be harmful to our health.”
A total of 1,003 study participants, average age 45 and nearly half women, answered food questionnaires and underwent CT scans to measure body fat changes.
Over a six-year follow-up period, independent of other factors, researchers found visceral fat volume increased by:
649 centimeters cubed for occasional drinkers; 707 centimeters cubed for frequent drinkers; and
852 centimeters cubed for those who drank one beverage daily.
Sugar-sweetened beverages, with sucrose or high fructose corn syrup — two of the most common sugars found in these popular drinks — include caffeinated and decaffeinated soda, carbonated and non-carbonated drinks with added sugar, fruit juice, and lemonade.
What you eat can influence sleep quality
A new study has found that eating less fibre, more saturated fat and more sugar is associated with lighter, less restorative, and more disrupted sleep.
Results show that greater fibre intake predicted more time spent in the stage of deep, slow wave sleep. In contrast, a higher percentage of energy from saturated fat predicted less slow wave sleep. Greater sugar intake also was associated with more arousals from sleep.
“It was most surprising that a single day of greater fat intake and lower fibre could influence sleep,” said principal investigator Marie-Pierre St-Onge.
Study results are published in the January issue of the Journal of Clinical Sleep Medicine.
The study also found that participants fell asleep faster after eating fixed meals provided by a nutritionist, which were lower in saturated fat and higher in protein than self-selected meals. It took participants an average of 29 minutes to fall asleep after consuming foods and beverages of their choice, but only 17 minutes to fall asleep after eating controlled meals.
“The finding that diet can influence sleep has tremendous health implications, given the increasing recognition of the role of sleep in the development of chronic disorders such as hypertension, diabetes and cardiovascular disease,” said St-Onge.
Leafy greens prevent glaucoma
A diet high in leafy greens like lettuce could prevent blindness in later life.
People who ate at least 240mg of nitrate – which is found in vegetables like spinach – were 30 per cent less likely to develop glaucoma.
People would need to eat just two cupfuls of lettuce each day to achieve the same result.
New research, looking at the records of more than 100,000 middle aged people, suggests that thousands of cases of the disease could be prevented.
It is thought that leafy vegetables improve blood circulation to the optic nerve which is impaired in people with the glaucoma.
Glaucoma can develop slowly over a number of years causing gradual loss of vision from the periphery and typically causes sensitivity to light.
It develops so slowly that often people do not notice their peripheral vision is failing. The area of vision becomes narrower as the disease progresses.
Chronic open-angle glaucoma affects up to two in every 100 people over 40 years old and around five in every 100 people over 80 years old.
It is caused by a blockage in the eye preventing fluid from draining away and causing increased pressure.
However, Harvard researchers found that greater intake of dietary nitrate and green leafy vegetables was associated with a 20 percent to 30 percent lower risk from regular glaucoma and up to 50 per cent for glaucoma with central vision loss.
A study in 2014 showed that a diet high in leafy vegetables is also good for heart health.
Some nitrates are used as medication for angina, as they dilate the blood vessels.
The NHS recommends leafy greens as part of a balanced diet.
The research was published online by JAMA Ophthalmology.
Nine of ten restaurant meals exceed recommended calories for a single meal
Just in time for Toronto’s Winterlicious comes research showing that 92 per cent of restaurants, chain and non-chain, serve oversize portions.
Tufts University researchers analyzed meals at 364 restaurants in Boston, San Francisco and Little Rock, Ark.
The cuisine included American, Chinese, Greek, Indian, Italian, Japanese, Mexican, Thai and Vietnamese fare. American, Chinese and Italian had the highest calorie counts with a mean of 1,495 calories per meal.
In 123 restaurants, the research team found that a single meal serving, without beverages, appetizers, or desserts sometimes exceeded the caloric requirements for an entire day.
“Making healthy choices while eating out is difficult because the combination of tempting options and excessive portions often overwhelm our self-control,” said study author Susan Roberts.
“Although fast-food restaurants are often the easiest targets for criticism because they provide information on their portion sizes and calories, small restaurants typically provide just as many calories, and sometimes more,” she said.
“Favourite meals often contain three or even four times the amount of calories a person needs, and although in theory we don’t have to eat the whole lot in practice most of us don’t have enough willpower to stop eating when we have had enough.”
Part of the problem, says study co-author William Masters, is that “standard meals are sized for the hungriest customers, so most people need superhuman self-control to avoid overeating. There is a gender dimension here that is really important: women typically have a lower caloric requirement than men, so on average need to eat less.
Women, while dining out, typically have to be more vigilant.”
So don’t blame yourself if you do overeat.
“All we have to do is see and smell food and our sympathetic nervous system revs up, insulin secretion drops blood glucose and our stomach relaxes,” said Roberts, “the goal of these physiological changes being to prepare us to eat all the food within reach. We order our favorite dishes because that is what tempts us, and then we eat more than we need because the portion is too large.”