Diets high in salt could deplete calcium in the body

ScienceDaily (July 24, 2012) — When sodium leaves a body, it takes calcium along with it, creating risk for kidney stones and osteoporosis.

See Also:Health & MedicineOsteoporosisFood AdditivesWomen's HealthPlants & AnimalsBiologyMolecular BiologyBiotechnologyReferenceElectrolyteDietary mineralKidney stoneSaliva

The scientific community has always wanted to know why people who eat high-salt diets are prone to developing medical problems such as kidney stones and osteoporosis.

Medical researchers at the University of Alberta may have solved this puzzle through their work with animal lab models and cells.

Principal investigator Todd Alexander and his team recently discovered an important link between sodium and calcium. These both appear to be regulated by the same molecule in the body. When sodium intake becomes too high, the body gets rid of sodium via the urine, taking calcium with it, which depletes calcium stores in the body. High levels of calcium in the urine lead to the development of kidney stones, while inadequate levels of calcium in the body lead to thin bones and osteoporosis.

"When the body tries to get rid of sodium via the urine, our findings suggest the body also gets rid of calcium at the same time," says Alexander, a Faculty of Medicine & Dentistry researcher whose findings were recently published in the peer-reviewed journal American Journal of Physiology -- Renal Physiology.

"This is significant because we are eating more and more sodium in our diets, which means our bodies are getting rid of more and more calcium. Our findings reinforce why it is important to have a low-sodium diet and why it is important to have lower sodium levels in processed foods."

It's been known for a long time that this important molecule was responsible for sodium absorption in the body, but the discovery that it also plays a role in regulating calcium levels is new.

"We asked a simple question with our research -- could sodium and calcium absorption be linked? And we discovered they are," says Alexander.

"We found a molecule that seems to have two jobs -- regulating the levels of both calcium and sodium in the body. Our findings provide very real biological evidence that this relationship between sodium and calcium is real and linked."

In their research, the team worked with lab models that didn't have this important molecule, so the models' urine contained high levels of calcium. Because calcium was not absorbed and retained by the body, bones became thin.

A journal editorial written about this research discovery noted the molecule could be a drug target to one day "treat kidney stones and osteoporosis."

The primary funder of the research was the Kidney Foundation of Canada.

"We are proud to support the research of Dr. Todd Alexander," said Wim Wolfs, National Director of Research of The Kidney Foundation of Canada. "Data in the United States shows that nearly 10% of adults will have a kidney stone at least once in their life. The prevalence of kidney stones also seems to be increasing in the U.S., which may be attributed to high rates of obesity and diabetes, along with possibly increased salt intake."

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Effect of three common diets on energy expenditure following weight loss detailed

ScienceDaily (June 26, 2012) — In an examination of the effect on energy expenditure and components of the metabolic syndrome of 3 types of commonly consumed diets following weight loss, decreases in resting energy expenditure and total energy expenditure were greatest with a low-fat diet, intermediate with a low-glycemic index diet, and least with a very low-carbohydrate diet, suggesting that a low-fat diet may increase the risk for weight regain compared to the other diets, according to preliminary research published in the June 27 issue of JAMA.

See Also:Health & MedicineDiet and Weight LossObesityFitnessNutritionCholesterolTriglyceridesReferenceSouth Beach dietZone dietGlycemic indexDetox diet

"Many people can lose weight for a few months, but most have difficulty maintaining clinically significant weight loss over the long term. According to data from the National Health and Nutrition Examination Survey (1999-2006), only 1 in 6 overweight and obese adults report ever having maintained weight loss of at least 10 percent for 1 year," according to background information in the article. One explanation for the poor long-term outcome is that weight loss elicits biological adaptations -- specifically a decline in energy expenditure and an increase in hunger -- that promote weight. According to the authors, the effect of dietary composition on energy expenditure during weight-loss maintenance has not been studied.

Cara B. Ebbeling, Ph.D., of Children's Hospital Boston, and colleagues conducted a study to evaluate the effects of 3 weight-loss maintenance diets on energy expenditure, hormones, and components of the metabolic syndrome. The study, conducted between June 2006 and June 2010, included 21 overweight and obese young adults. After achieving 10 percent to 15 percent weight loss while consuming a run-in diet, participants consumed an isocaloric low-fat diet (60 percent of energy from carbohydrate, 20 percent from fat, 20 percent from protein; high glycemic load), low-glycemic index diet (40 percent from carbohydrate, 40 percent from fat, and 20 percent from protein; moderate glycemic load), and very low-carbohydrate diet (10 percent from carbohydrate, 60 percent from fat, and 30 percent from protein; low glycemic load) in random order, each for 4 weeks. The primary outcome measured was resting energy expenditure (REE), with secondary outcomes of total energy expenditure (TEE), hormone levels, and metabolic syndrome components.

The researchers found that energy expenditure during weight-loss maintenance differed significantly among the 3 diets. The decrease in REE from pre-weight-loss levels, measured by indirect calorimetry in the fasting state, was greatest for the low-fat diet (average relative to baseline, -205 kcal/d), intermediate with the low-glycemic index diet (-166 kcal/d), and least for the very low-carbohydrate diet (-138 kcal/d). The decrease in TEE also differed significantly by diet (average -423 kcal/d for low fat; -297 kcal/d for low glycemic index; and -97 kcal/d for very low carbohydrate).

"Hormone levels and metabolic syndrome components also varied during weight maintenance by diet (leptin; 24-hour urinary cortisol; indexes of peripheral and hepatic insulin sensitivity; high-density lipoprotein

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Significant cardiovascular risk with Atkins-style diets, experts warn

ScienceDaily (June 27, 2012) — Women who regularly eat a low carbohydrate, high protein diet are at greater risk of cardiovascular disease (such as heart disease and stroke) than those who do not, a study just published on the British Medical Journal website suggests.

See Also:Health & MedicineDiet and Weight LossObesityNutritionHeart DiseaseCholesterolStroke PreventionLiving WellReferenceZone dietColostrumSouth Beach dietGlycemic index

Although the actual numbers are small (an extra 4-5 cases of cardiovascular disease per 10,000 women per year) the authors say that this is a 28% increase in the number of cases and that these results are worrying in a population of young women who may be exposed to these dietary patterns and face the excess risk for many years.

Low carbohydrate-high protein diets are frequently used for body weight control. Although they may be nutritionally acceptable if the protein is mainly of plant origin (e.g. nuts) and the reduction of carbohydrates applies mainly to simple and refined ones (i.e. unhealthy sweeteners, drinks and snacks), the general public do not always recognise and act on this guidance.

Studies on the long term consequences of these diets on cardiovascular health have generated inconsistent results. So a team of international authors carried out a study on just under 44,000 Swedish women aged between 30 and 49 years from 1991-92 (with an average follow-up of 15 years).

Women completed an extensive dietary and lifestyle questionnaire and diet was measured on the low carbohydrate-high protein (LCHP) score where a score of two would equal very high carbohydrate and low protein consumption through to 20 which would equal very low carbohydrate and high protein consumption.

Factors likely to influence the results were taken into account including smoking, alcohol use, diagnosis of hypertension, overall level of activity and saturated / unsaturated fat intake.

After these variables were included, results showed that 1270 cardiovascular events took place in the 43,396 women (55% ischaemic heart disease, 23% ischaemic stroke, 6% haemorrhagic stroke, 10% subarachnoid haemorrhage and 6% peripheral arterial disease) over 15 years.

The incidence of cardiovascular outcomes increased with an increasing LCHP score.

Unadjusted figures show that, compared with an LCHP score of six or less, cardiovascular diseases increased by 13% for women with a score from 7 to 9, to 23% for those with a score from 10 to 12, to 54% for those with a score from 13 to 15, and to 60% for those with a score of 16 or higher.

After adjusting for other cardiovascular risk factors, there was still a significant 5% increase in the likelihood of a cardiovascular event or death with every two point increase in the LCHP score. The 5% increase resulted from a daily decrease of 20g of carbohydrates (equivalent to a small bread roll) and a daily increase of 5g of protein (equivalent to one boiled egg).

In absolute terms, the adjusted figures represent an additional four to five cases of cardiovascular diseases per 10,000 women per year compared with those who did not regularly eat a low carbohydrate, high protein diet.

Increasing level of education and physical activity reduced the risk of cardiovascular disease whilst increasing levels of smoking increased the risk.

The authors conclude that LCHP diets "used on a regular basis and without consideration of the nature of carbohydrates or the source of proteins" are associated with cardiovascular risk. This study doesn't, however, address the questions concerning the possible benefit of short-term effects of LCHP diets that can be used to control weight or insulin resistance, which the authors say needs further investigation.

An accompanying editorial argues that the short term benefits of weight loss seem outweighed by longer term cardiovascular harms. Anna Floegel from the German Institute of Human Nutrition and Tobias Pischon from the Max Delbrück Center for Molecular Medicine in Germany, say that the discrepancy between conclusions from different types of studies in this field "need to be resolved before low carbohydrate-high protein diets can be safely recommended to patients."

In the meantime, they suggest that any benefits gained from these diets in the short-term "seem irrelevant in the face of increasing evidence of higher morbidity and mortality from cardiovascular diseases in the long term."

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'Atkins'-Type Diets May Raise Risk of Heart Problems: Study

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Long-Term Salty Diets Tied Again to High Blood Pressure

HealthDay – 4 hrs ago MONDAY, June 18 (HealthDay News) -- Indulging in a bag of chips or munching a handful of nuts now and then isn't likely to hurt you in the short run, but regularly chowing down on salty foods over several years may damage your blood vessels and lead to high blood pressure, a new study finds.

Researchers reporting in the June 18 online edition of Circulation said that eating too much salt over time may affect the lining of blood vessels, increasing the likelihood of developing high blood pressure.

"This study reinforces guidelines backed by the American Heart Association and other professional organizations that recommend reducing salt consumption to reduce your risk of developing high blood pressure," said Dr. John Forman, lead author of the study and assistant professor of medicine at Harvard Medical School in Boston.

High blood pressure, also called hypertension, can contribute to heart failure, stroke and kidney failure.

Researchers tracked the salt intake of 5,556 white men and women from the Netherlands over about six years. None of the participants had high blood pressure at the study's start.

By analyzing 24-hour urine samples collected periodically over several years, the researchers noted the amount of uric acid and albumin in the urine, markers of blood vessel damage. They also tracked the amount of salt, or sodium, the participants ate by measuring how much sodium ended up in their urine.

The researchers found that, over time, people who ingested more sodium had more uric acid and albumin in their urine.

The higher the levels of uric acid and albumin, the more likely those people were to develop high blood pressure if they continued on high-sodium diets, the investigators found. Over the approximately six-year period of the study, 878 new cases of hypertension (high blood pressure) were discovered.

Compared with the participants eating the least amount of sodium (about 2,200 milligrams a day), those eating the most (6,200 mg a day) were 21 percent more likely to develop high blood pressure. Those who had high uric acid and albumin levels and ate the most salt were 86 percent more likely to develop high blood pressure.

How much salt is 2,200 milligrams of salt? About a teaspoon.

Much of the sodium the average American consumes comes from processed foods. Forman cautions that people who don't use salt shakers at the table shouldn't assume they're not getting too much sodium. One cup of soup or a single-serving frozen dinner can have 1,000 milligrams of sodium.

The study showed an association between the markers of blood vessel damage and high blood pressure, but not a cause-and-effect relationship.

Dr. Gregg Fonarow, professor of cardiovascular medicine at the University of California, Los Angeles, said, "the research shows that in some individuals, there is an association between these markers -- uric acid and albumin -- and the subsequent diagnosis of hypertension."

Why salt causes blood vessel damage -- called "endothelial dysfunction" -- is not fully understood, said Fonarow. "Sodium exposure may lead to progressive changes in the lining of the blood vessels, eventually becoming irreversible," he said.

"And once you've developed hypertension, lowering your salt intake most likely won't be enough to normalize your blood pressure," he said.

The study also suggests that those with markers of blood vessel damage may be more negatively affected by a high-salt diet than others.

The idea that salt influences the development of high blood pressure is considered controversial by some experts. A study published last year in the Journal of the American Medical Association suggested that lower amounts of sodium in urine were associated with more cardiovascular disease deaths.

In order to link high salt intake more closely to blood vessel damage and subsequent high blood pressure, Forman said it would be necessary to follow many people over about 20 years, ideally using ultrasound to directly assess blood vessel health.

Fonarow said the key to high blood pressure prevention is moderation and watchful management of other cardiovascular risks. "Avoid a high-salt diet, but also don't smoke, watch your weight, keep your cholesterol down and manage your blood pressure," he said. "Those factors are probably even more important."

Heart experts advise limiting sodium intake to less than 2,300 mg a day, or 1,500 mg if you're black, over 50 years old or have certain chronic diseases. By reading Nutrition Facts labels closely, you can limit your sodium intake.

More information

The U.S. National Library of Medicine has more about high blood pressure.

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Anthropologists discover new research use for dental plaque: Examining diets of ancient peoples

ScienceDaily (May 2, 2012) — While we may brush and floss tirelessly and our dentists may regularly scrape and pick at our teeth to minimize the formation of plaque known as tartar or dental calculus, anthropologists may be rejoicing at the fact that past civilizations were not so careful with their dental hygiene.

See Also:Health & MedicineDentistryBone and SpinePlants & AnimalsNatureBiologyFossils & RuinsAncient CivilizationsFossilsReferenceCarbon-14Periodontal diseaseRadiocarbon datingDentistry

University of Nevada, Reno researchers G. Richard Scott and Simon R. Poulson discovered that very small particles of plaque removed from the teeth of ancient populations may provide good clues about their diets. Scott is chair and associate professor of anthropology in the College of Liberal Arts. Poulson is research professor of geological sciences in the Mackay School of Earth Sciences and Engineering.

Scott obtained samples of dental calculus from 58 skeletons buried in the Cathedral of Santa Maria in northern Spain dating from the 11th to 19th centuries to conduct research on the diet of this ancient population. After his first methodology met with mixed results, he decided to send five samples of dental calculus to Poulson at the University's Stable Isotope Lab, in the off chance they might contain enough carbon and nitrogen to allow them to estimate stable isotope ratios.

"It's chemistry and is pretty complex," Scott explained. "But basically, since only protein has nitrogen, the more nitrogen that is present, the more animal products were consumed as part of the diet. Carbon provides information on the types of plants consumed."

Scott said that once at the lab, the material was crushed, and then an instrument called a mass spectrometer was used to obtain stable carbon and nitrogen isotope ratios.

"It was a long shot," he said. "No one really thought there would be enough carbon and nitrogen in these tiny, 5- to 10- milligram samples to be measurable, but Dr. Poulson's work revealed there was. The lab results yielded stable carbon and nitrogen isotope ratios very similar to studies that used bone collagen, which is the typical material used for this type of analysis."

Scott explained that the common practice of using bone to conduct such research is cumbersome and expensive, requiring several acid baths to extract the collagen for analysis. The process also destroys bone, so in many instances, it isn't permitted by museum curators.

As for using hair, muscle and nails for such research, Scott said, "They are great, when you can find them. The problem is, they just don't hold up very well. They decompose too quickly. Dental calculus, for better or for worse, stays around a very long time."

Scott said that although additional work is necessary to firmly establish this new method of using dental calculus for paleodietary research, the results of this initial study indicate it holds great potential.

"This is groundbreaking work," Scott said. "It could save a lot of time and effort, and also allow for analysis when things like hair, muscle and nails are no longer available."

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Study Weighs In on Diets for Kids

HealthDay – 1 hr 17 mins ago FRIDAY, March 30 (HealthDay News) -- If you're trying to get your child to drop a few pounds, here's some food for thought: A new study finds that among three types of diets, kids preferred the one emphasizing foods that don't cause blood-sugar imbalances.

Kids also lost weight on the other two diets, however.

"We know the diets are effective. The question now is how we can get people to follow them," said study lead author Shelley Kirk, a dietitian and assistant professor of clinical pediatrics at the University of Cincinnati College of Medicine.

About 20 percent of children aged 6 to 11 in the United States are obese, which is a step beyond simply being overweight, according to statistics from the U.S. Centers for Disease Control and Prevention. The rate is similar in adolescents aged 12 to 19.

In the new study, researchers examined 85 obese 7- to 12-year-olds who accepted an assigned diet for a year. The kids had weekly dietary counseling and biweekly exercise sessions for the first three months, and then were on their own for the remaining nine months.

One of the diets is similar to the Atkins diet for adults, and focused on very low carbohydrate consumption and a lot of high-protein foods. Another diet focused on foods with low glycemic indexes (such as fruit, nonstarchy vegetables, whole grains, poultry and fish) that are less likely to cause blood-sugar levels to fluctuate. The third diet focused on controlling food portions and making sure calories overall were 55 percent to 60 percent carbohydrates, 10 percent to 15 percent protein, and 30 percent fat.

The researchers found that the participants on average lowered their body mass index (BMI) -- a measurement of body fat based on height and weight -- and the percentage of fat in their bodies. Their waist sizes didn't decrease after a year, but it's not clear if that's because they grew.

The children had the most difficulty following the low-carbohydrate diet and the easiest time with the low-glycemic diet, Kirk said.

Overall, most of the kids lost weight on the diets, Kirk noted.

Cathleen Davis, a clinical dietitian and nutritionist who works with children at Good Samaritan Hospital Medical Center in Babylon, N.Y., applauded the study and explained why the diets might have differed in popularity.

She said the portion-controlled and low-glycemic diets are probably better tolerated "because they both are more mainstream diets that the parents would be familiar and comfortable with."

What should you do if you'd like to put your child on a diet?

"Ask your pediatrician about local reputable programs and look on Eatright.org to find a registered dietitian serving your area," Davis said. "Make tiny changes and expect bad days -- absolutely no one eats perfectly 100 percent of the time. And be very careful of programs that push supplements, make any type of claim for immediate success and don't have licensed credentials."

The study was released online March 1 in advance of publication in an upcoming print issue of the Journal of Pediatrics.

More information

For more about kids and obesity, try the U.S. Centers for Disease Control and Prevention.

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Best Fat Burning Diets

March 25th, 2012

All foods that you simply eat have calories and once you eat a lot more calories than your physique can burn, then fat deposits increase. There are many fat burning diets to chose from nowadays. To burn fat, the very best issue to complete is modifying your diet. You’ll need to begin by reducing calories, sodium, and fat. You’ll find three things that lead to physique fat: calorie intake, late night consuming and not sufficient exercise.

Not obtaining sufficient exercise will lead your body to build up unnecessary fat and limits your metabolism speed. The body’s metabolism has to reach a sure speed to burn fat. A method to speed up your metabolism would be to eat more regularly. Eat 4-5 smaller meals every day as an alternative to 2-3.

These are 10 recommended foods in fat burning diets: Cayenne pepper, ginger, citrus fruit, apples, bananas, dairy, garlic and cinnamon.

Don’t think that by only eating these foods, you’ll merely lose fat. You may will need to alter your diet and exercise. To burn probably the most fat, it really is critical to eat in moderation, limit saturated fats, eat fruits and vegetables and raise your metabolism

Foods which have fantastic amounts of Vitamin C act as fat burners. Some include limes, oranges, broccoli, celery and watermelon. Broccoli and cabbage have the highest amount of Vitamin C. The Vitamin C dilutes and weakens the fat producing it less complicated to be flushed out of the physique.

Water has always been the number one choice in fat burning diets. It is natural, suppresses your appetite and gets rid of excess sodium inside the physique. It also helps to improve the metabolic rate.

Now, it is your call to get the motivation to start burning fat as quickly as possible and enjoy a healthier life.

Note: By researching and comparing the best fat burning supplement products in the market, you will determine the one that is safe and right for you.

Natural products have proven to be very effective.

You are very welcome to visit the Fat Burning Supplements website

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