STUDY: Older men's sperm is more prone to genetic defects than that of younger men, according to a new study.

JOURNAL: American Society for Reproductive Medicine

AUTHORS: Dr. Narendra Singh

ABSTRACT: Men who put their career before having a family should beware: the ticking of the biological clock is as important for fertility in men as it is in women.

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COMMENTARY: American scientists have discovered that genetic damage to sperm routinely starts to cause infertility in men as young as 35.

The strongest biological evidence yet for a significant drop in male fertility in the late thirties is a warning to the increasing number of grey-haired fathers who are leaving it later to have children.

The popular worry that career women risk losing the chance to have children has long been supported by infertility research focusing on how the quality of women’s eggs deteriorates with age.

Researchers from the University of Washington in Seattle have now provided the first firm molecular explanation for why childless career men should worry too. The chances of having a baby are reduced if the man is in his late thirties or forties.

Dr Singh’s team found that, whatever the sperm count, its genetic quality was closely related to age, with a cut-off point for serious damage of about 35.

Men in the older group had higher concentrations of sperm with broken strands of DNA, more acute levels of such genetic damage and their immune systems were much less efficient at weeding out faulty sperm by programmed cell suicide, or apoptosis. The sperm of the older men were also less vigorous swimmers.

Men concerned about their fertility should avoid activities such as smoking that may damage the DNA of their sperm. While there’s nothing anyone can do about getting older, men who want to retain their own best capacity to father children should try to minimise contact with toxic agents and maintain a healthy lifestyle.

The findings do not suggest that most men who wait until after 35 to try for children will have problems, particularly if the man’s partner is in her twenties or early thirties. But the study does alert fertility doctors to another potential problem when older couples have difficulty in conceiving.

STUDY: Effective treatment for people with hepatitis B

JOURNAL: Southeast Asian Journal of Tropical Medicine and Public Health (2001;32:140–2

AUTHORS:

ABSTRACT: According to a new study published in the Southeast Asian Journal of Tropical Medicine and Public Health (2001;32:140–2), an herbal formula containing Phyllanthus amarus is an effective treatment for people with hepatitis B.

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In fact, the herbal formula compared favorably with interferon, the standard medical treatment for the condition.

COMMENTARY: In this new study, 30 patients with hepatitis B infection were treated with four capsules three times per day of an herbal formula for three months.

Roughly 75% of people taking the herbal formula had normalization of blood measures of liver damage. Over 40% of those treated had no evidence of continued infection after treatment. All the measured outcomes were similar to, or better than, the results in 25 people treated with interferon.

The herbal formula contained 275 mg of Phyllanthus amarus per capsule and an unspecified amount of Panax notoginseng, as well as other unspecified ingredients. No side effects of the herbal treatment were reported.

Phyllanthus has been shown in test tube studies to block the action of an enzyme necessary for the hepatitis B virus to reproduce. The role of the other herbs in this formula is as yet unclear.

Hepatitis B is a viral infection of the liver, and can cause liver failure, cancer, or both in up to 25% of the people who carry the virus. Hepatitis B may be spread by exposure to infected blood or other body fluids; typically from sexual contact, IV drug use, or occupational exposure of healthcare workers.

As not all infected individuals experience symptoms, many hepatitis B carriers are unaware that they are infected. An estimated 1.25 million Americans currently carry the hepatitis B virus. Infection rates are far higher in other parts of the world, particularly Southeast Asia and sub-Saharan Africa.

The standard treatment for hepatitis B is interferon, given by injection three times per week for four to six months. Interferon treatment can cause a number of side effects, including flu-like symptoms, depression, weight loss, and autoimmune disease. Less than a quarter of infected people are cured by interferon treatment, with another 25 to 45% experiencing symptomatic improvement.

Make sure to see a doctor if you have Hep B or C.

STUDY:

JOURNAL: Am J Clin Nutr. 2002;76:365-372

AUTHORS: David J. A. Jenkins

ABSTRACT: Compared with a dairy diet, a soy-based diet improved lipid profile, yielding a calculated reduction in coronary artery disease (CAD) risk, according to a study published in the American Journal of Clinical Nutrition.

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COMMENTARY: "Many of the benefits of soy have been attributed to soy isoflavones," write David J. A. Jenkins, from St. Michael's Hospital in Toronto, Ontario, and colleagues.

Study subjects included 23 men and 18 postmenopausal women with elevated cholesterol levels who rotated through three one-month diets that were all very low in saturated fat (less than 5% of energy and less than 50 mg/day of cholesterol). Protein sources were low-fat dairy products and egg substitute in the control diet, and low-fat soymilk and a variety of soy-based meat substitutes such as soy hot dogs and tofu burgers in the two soy protein-containing diets. The high-isoflavone diet contained 50 g soy protein and 73 mg isoflavones daily, and the low-isoflavone diet contained 52 g soy protein and 10 mg isoflavones daily.

Although serum concentrations of low-density lipoprotein (LDL) cholesterol were lower after the high-isoflavone diet, there were no major differences between the high- and low-isoflavone soy protein diets in their beneficial effects. After each soy diet, total cholesterol, LDL to high-density lipoprotein (HDL) ratio cholesterol, homocysteine concentrations, and systolic blood pressure in men were lower than they were after the control diet. Overall CAD risk calculated from blood lipid and blood pressure changes was 10.1%+/-2.7% lower with the soy diets than with the control diet.

STUDY: Neuropathy and Statins

JOURNAL: Neurology 2002;58:1321-1322, 1333-1337

AUTHORS: Dr. Michael Donaghy

ABSTRACT: Cholesterol-lowering drugs called statins may increase the risk of nerve damage called neuropathy, researchers from Denmark suggest.

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COMMENTARY: But the well-known benefits of statins far outweigh the risk of neuropathy, which remains very low, the study's authors point out.

Peripheral neuropathy occurs when nerves in the peripheral nervous system--those outside of the brain and spinal cord--become damaged. Symptoms vary but may include tingling, numbness and burning pain as well as decreased sensitivity to temperature or pain. Diabetes, kidney disease, thyroid disease and alcohol abuse can all lead to neuropathy, but the nerve damage, known as polyneuropathy when it affects more than one nerve, may develop independently of these conditions.

As more and more people have started taking statins on a long-term basis, a small number of patients have developed cases of nerve damage with no apparent obvious cause. In a previous study, Dr. David Gaist, of the University of Southern Denmark in Odense, found that statins increased the risk of polyneuropathy, but the study was too small to be definitive.

Now, Gaist and his colleagues report the results of a larger study that seems to confirm the link between statins and neuropathy. In the population-based study in a Danish county, the researchers identified 166 first-time cases of neuropathy that did not have an obvious cause.

The cases were divided into definite, probable and possible cases depending on how certain the researchers were that the nerve damage could not have been caused by some other condition. Nine of the patients had taken statins, with the average length of treatment being nearly 3 years.

Compared to a "control" group of people who did not have neuropathy, people who had taken statins were 4 to 14 times more likely to develop polyneuropathy that did not have a known cause, according to the report published in the May 14th issue of the journal Neurology.

Several of the statins taken by patients in the study list peripheral neuropathy as a possible side effect. However, even though statins may increase the risk of developing nerve damage, the findings should not discourage the use of the cholesterol-lowering drugs, according to Gaist.

"The positive benefits of statins, particularly on reducing the risk of heart disease, far outweigh the potential risk of developing neuropathy," he said in a news release.

According to Gaist, "These findings shouldn't affect doctor or patient decisions to start using statins. But if people who take statins develop neuropathy symptoms, they should talk with their doctor, who may reconsider the use of statins."

"The overwhelming consideration is that, for those many patients for whom they are indicated, statins seem to provide a major reduction in the incidence of heart attack and stroke, and the many deaths associated with these disorders," Dr. Michael Donaghy, of the University of Oxford in the UK, told Reuters Health.

Any side effects of the drugs must be weighed against this "very substantial benefit," according to Donaghy, who is the author of a related editorial.

Donaghy notes that the study shows that polyneuropathy occurs in 1 out of every 2,200 patients who take statins. This nerve damage likely includes numbness, tingling and pain in the hands and feet, the Oxford physician points out. Although the severity of the neuropathy in patients taking statins is uncertain, Donaghy said it is "unlikely" to cause the same level of disability as a stroke, which might be prevented by statin use.

"Thus, the overall benefit-risk ratio of statins remains firmly in favor of using them in those patients for whom they are indicated to prevent cardiovascular disease," he concluded.

STUDY: Study finds vegetables in allium family beneficial

JOURNAL: Journal of the National Cancer Institute

AUTHORS: Ann Hsing

ABSTRACT: A study found that men who ate about a tenth of an ounce or more a day of garlic were about 50 percent less likely to have prostate cancer.

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COMMENTARY: Men in China have the lowest rate of prostate cancer in the world, and a diet rich in garlic, shallots and onions may be one of the reasons. Researchers at the National Cancer Institute report in a new study that a diet with lots of vegetables from the pungent allium food group reduces the risk of prostate cancer by about half. And the common Chinese diet includes hearty servings of these vegetables.

The results showed that those who ate more than a third of an ounce a day from the allium food group — which consists of onions, garlic and shallots — were about 50 percent less likely to have prostate cancer than those who ate less of the foods.

Scallions seemed to be the most protective food in the group. According to the study, men who ate about a tenth of an ounce or more a day of scallions reduced their prostate cancer risk by about 70 percent. For garlic consumption of the same amount, the prostate cancer risk was reduced by about 53 percent.

The typical Chinese diet is much more heavily seasoned with garlic, scallions and onions than is the traditional American diet. But even so, the amount of allium vegetables consumed is measured only in fractional ounces. For instance, the study suggests that an effective level of prostate cancer protection can be achieved with about one clove of garlic a day.

Earlier studies have found that that eating tomatoes and tomato products can lower the risk of prostate cancer. Italy, where tomato sauce and garlic are favorites, has one of the lowest rates of prostate cancer in Europe.

This shows that your mother was right.

Eat more vegetables.

STUDY: What can we eat?

JOURNAL: Environmental Working Group

AUTHORS: Jane Houlihan

ABSTRACT: Farmed salmon, which Americans are scarfing down because it is supposed to be healthy, may actually be carrying high levels of cancer-causing chemicals called PCBs.

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COMMENTARY: Wild salmon fished out of rivers and streams may actually be healthier for the time being.

Farmed salmon filets from 10 grocery stores in Washington, San Francisco, and Portland, Oregon, were tested and seven were contaminated with high levels of polychlorinated biphenyls.

"These first-ever tests of farmed salmon from U.S. grocery stores show that farmed salmon are likely the most PCB-contaminated protein source in the U.S. food supply," the group, a non-profit organization that investigates environmental matters, said in a statement.

"EWG's analysis of seafood industry fish consumption data shows that one quarter of all adult Americans (52 million people) eat salmon, and about 23 million of them eat salmon more often than once a month," the group said in a statement.

"Based on these data we estimate that 800,000 people face an excess lifetime cancer risk ... from eating farmed salmon."

They called on the U.S. Food and Drug Administration to do its own study and issue health warnings as needed.

They said their findings are supported by other studies done in Canada, Ireland and Britain.

PCBs come from hydraulic fluids and oils, electrical capacitors and transformers.

They are endocrine disrupters -- chemicals that act like hormones. They and related chemicals known as dioxins can cause cancer, infertility and perhaps other sexual changes.

STUDY: Popular procedure may have hidden risks,studies find

JOURNAL: Obstetrics & Gynecology

AUTHORS: Dr. Evan Myers

ABSTRACT: An increasingly popular treatment promises to rid women of painful, bleeding uterine fibroids without standard surgery’s risks. But new research has some doctors questioning how long the treatment helps — and if it’s too risky for women who hope to become pregnant.

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COMMENTARY: Part of the problem is that this new “uterine artery embolization” has never been fully studied to see how it compares with uterine-sparing surgical removal of fibroids.

But the controversy highlights a bigger issue: “We really don’t know very much at all about how to manage fibroids,” says Dr. Evan Myers of Duke University — even though the uterine growths plague more than a million women a year and are the leading cause of hysterectomies.

Nearly 40 percent of women in their 30s and 40s develop fibroids, non-cancerous growths of muscle fibers inside the uterus. No one knows what causes fibroids, and tiny ones usually cause no symptoms. But they can grow to cantaloupe size, causing severe pain, heavy bleeding and infertility or pregnancy complications.

More than 150,000 hysterectomies — surgical uterus removal — each year are due to fibroids.

For women who still want children, options are limited. Drugs shrink fibroids only temporarily. About 35,000 women a year undergo myomectomy, where surgeons remove fibroids while leaving the uterus intact. But it’s painful, fibroids sometimes grow back, and women who later become pregnant usually require Caesarean deliveries.

Uterine artery embolization, or UAE, is a far less invasive alternative.

Doctors squirt tiny plastic pellets into certain uterine arteries, cutting off the blood supply feeding the fibroids. Over the next three months to a year, the fibroids shrink.

About 85 percent of patients get relief, fueling UAE’s growing popularity. Some 30,000 embolizations have been performed since UAE was first tried in 1995, says Myers, who calls it a promising procedure.

But studies published this month in Obstetrics & Gynecology raise questions about how long that relief lasts — and stress that contrary to public perception, UAE isn’t risk-free.

The University of California, Los Angeles, tracked 59 UAE patients and another 38 who had a myomectomy. Three years later, 29 percent of the UAE patients needed further fibroid treatment; only 3 percent of myomectomy patients did.

Infection, bleeding and blood-vessel clots are considered serious but rare risks of UAE — at least two deaths have been reported since 1995 — although no one knows how often complications occur.

Georgetown University Hospital tracked 400 embolization patients treated there since 1997, and concluded the overall risk of side effects was a low 5 percent. Most were minor — but five patients required days of hospitalization for infection, bleeding or clots. One needed a hysterectomy four months after her UAE, for heavy bleeding when her body expelled a shrunken fibroid. Researchers at Thomas Jefferson University analyzed the 50 published cases of pregnancy after UAE and concluded those women had higher risks of miscarriage, post-delivery hemorrhage, premature birth, breech babies and Caesarean sections than do healthy women. Other researchers say infertility also may be a risk if UAE accidentally blocks blood flow to the ovaries.

Meanwhile, any of the options is reasonable for a woman no longer considering pregnancy, but know that retreatment rates for both UAE and myomectomy remain in question, Myers says.

If women want to become pregnant, they “really need to know they’re taking a chance” with UAE, he adds. Georgetown’s Spies recommends myomectomy in particular for anyone wanting a baby within two years, because UAE shrinks fibroids so slowly.

"Do a little digging” before picking a doctor, adds Cynthia Pearson of the National Women’s Health Network, which urges better fibroid research. “No matter how fabulous things were at Georgetown, a woman can’t assume her results will be the same” if her doctor hasn’t performed many UAEs.

STUDY: Elderly can think themselves into the grave, report finds

JOURNAL: the Journal of Personality and Social Psychology

AUTHORS: Becca Levy

ABSTRACT: Older people can literally think themselves into the grave by feeling bad about getting old.

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COMMENTARY: People who said they had more positive views about aging lived an average 7.6 years longer than those with negative perceptions.

How one feels about getting old is more important even than having low blood pressure or cholesterol.

The effect of more positive self-perceptions of aging on survival is greater than the physiological measures of low systolic blood pressure and cholesterol, each of which is associated with a longer lifespan of four years or less.

It is also greater than the independent contributions of lower body mass index, no history of smoking, and a tendency to exercise, each of these factors has been found to contribute between one and three years of added life.

The study carries two messages. The discouraging one is that negative self-perceptions can diminish life expectancy. The encouraging one is that positive self-perceptions can prolong life expectancy.

Let's all think positive!!!!!!

STUDY: CoQ10 and Asthma

JOURNAL: Allergy 2002;57:811-814.

AUTHORS: Dr. Frantisek Gazdik

ABSTRACT: Concentrations of coenzyme Q10 are significantly lower among patients with allergic asthma compared with controls, according to the results of a study by researchers from the Slovak Republic.

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COMMENTARY: Dr. Frantisek Gazdik from the Institute of Preventive and Clinical Medicine, Bratislava, and colleagues measured the levels of the antioxidants coenzyme Q10, alpha-tocopherol, and beta-carotene in 56 men and women with allergic asthma and in 25 healthy controls.

Compared with controls, the mean level of coenzyme Q10 among asthmatics was significantly lower at 0.34 mol/L versus 0.52 mol/L in plasma and 0.33 mol/L versus 0.50 mol/L in whole blood (p < 0.001), the researchers found.

The levels of alpha-tocopherol were also significantly decreased in asthmatics compared with controls, but there were no differences in levels of beta-carotene.

Dr. Gazdik's team notes that there was a positive correlation between whole blood coenzyme Q10 and alpha-tocopherol concentrations, and conclude that "the contribution of coenzyme Q10 to antioxidative dysbalance seems to be probable and could not be excluded."

The researchers say that the finding provides a rationale for coenzyme Q10 supplementation in this population.

STUDY:

JOURNAL: Arterioscler Thromb Vasc Biol 2003; 23:1066-1071.

AUTHORS: Dr. Helena J. Teede

ABSTRACT: Australian researchers have discovered one reason why isoflavone-rich diets appear to lower cardiovascular risks.

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COMMENTARY: A randomized crossover study in which 46 healthy men and 34 post-menopausal women between the ages of 45 and 75 years took red clover-derived isoflavones and placebo for two 6-week periods.

The treatment formulations predominantly contained either formononetin or biochanin, the isoflavones synthesized by red clover. Subjects were given a total daily dose of 80 mg.

Treatment with the formononetin-enriched isoflavones "significantly reduced arterial stiffness with improved systemic arterial compliance...attributable to a reduction in total peripheral resistance...and a corresponding reduction in central pulse wave velocity," the authors discovered.

"These effects may partly explain the lower cardiovascular risk in populations eating isoflavone-rich diets," they conclude.



Eat you soy !!!!

STUDY:

JOURNAL: Arch Intern Med 2003;163:1448-1453.

AUTHORS: Dr. David J. Maron

ABSTRACT: Daily use of capsules containing flavonoids found in green and black tea appears to produce a significant drop in total and LDL cholesterol levels.

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COMMENTARY: Flavonoid use has been shown to lower cholesterol levels in animal studies. There is also evidence from epidemiologic studies that tea consumption can lower such levels and protect against myocardial infarction.

The findings are based on a study of 240 subjects with mild to moderate hypercholesterolemia who were randomized to receive a daily capsule containing theaflavins and catechins or placebo for 12 weeks. All of the subjects were on a low-fat diet.

Treatment with the tea extracts was tied to a 11.3% and 16.4% drop in total and LDL cholesterol levels, respectively, compared with baseline values (p = 0.01 for both).

Tea extract use was also associated with a nonsignificant rise in HDL cholesterol levels and triglyceride levels. No significant change in any of these levels was noted in the placebo group.

STUDY: Inflammation is the key

JOURNAL: American Journal of Cardiology 08 2003

AUTHORS: Dr. Hecht

ABSTRACT: The rate at which plaque builds up in the coronary arteries seems to be unaffected by how much LDL ("bad") cholesterol is lowered using so-called statin drugs such as Zocor or Lipitor.

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COMMENTARY: As Dr. Harvey S. Hecht of Beth Israel Medical Center, New York, said, "the question of whether or not 'lower is better' for LDL cholesterol is unresolved."

His research suggests that "lower is not necessarily better," at least in patients who have hardening of the coronary arteries but who do not yet have symptoms.

Dr. Hecht, along with Dr. S. Mitchell Harman of Kronos Longevity Research Center, Phoenix, Arizona, came to this conclusion after studying 182 patients with "subclinical atherosclerosis."

The duo measured the amount of calcified plaque in the participants' coronary arteries, using a technique called electron beam tomography, before and after a year of lipid-lowering treatment with statins alone or in combination with niacin.

As the researchers explain in the American Journal of Cardiology, treatments that aimed to lower LDL cholesterol to 80 milligrams per deciliter (mg/dL) or less were deemed more aggressive, those with a target of greater than 80 mg/dL were deemed less aggressive.

Despite a greater improvement in LDL levels in the more aggressively treated group, the researchers found that annual rate at which plaque increased (9.3%) was no different from that in the less aggressively treated group (9.1%).

STUDY: Watch your teeth

JOURNAL: Stroke, August 1, 2003

AUTHORS: Dr. Moise Desvarieux

ABSTRACT: Previous studies have linked tooth loss with cardiovascular disease, but now, new findings indicate that it also occurs more often in people who have a build-up of cholesterol plaque in their arteries (atherosclerosis), but who don't have symptoms.

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COMMENTARY: In the Oral Infections and Vascular Disease Epidemiology Study (INVEST), Dr. Moise Desvarieux, from the University of Minnesota in Minneapolis, and colleagues evaluated periodontal disease, tooth loss, and plaque in the arteries of the neck in 711 subjects.

The subjects were 66 years of age, on average, and none had a history of stroke or heart attack. The severity of periodontitis was directly related to tooth loss.

In addition, the presence of plaque in the neck arteries was significantly associated with the extent of tooth loss. For example, 46% of subjects missing 9 or fewer teeth had such plaques, compared with about 60% of subjects missing 10 or more teeth.

However, plaques were actually less common among people missing 20 or more teeth than among those missing 10 to 19 teeth.

STUDY:

JOURNAL:

AUTHORS: William McCrea

ABSTRACT: Cardiac patients at a British hospital are being prescribed two glasses of red wine a day in the hope that this may prevent further heart complications.

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COMMENTARY: William McCrea, a heart surgeon at the Great Western Hospital in Swindon, west England, told the media the idea came from looking at the health statistics of France.

"As a nation they consume twice the amount of fat we do, they smoke more and don't do any more exercise than us, but their rate of deaths from heart attacks is half ours. What's the difference? They drink red wine like we drink tea."

Unfortunately for any of his wine-loving patients, McCrea also believes that cheaper red wines are best, as they will contain more antioxidants than top-quality wines that have been kept for years in the barrel.

His favourites are said to include Pinot Noir, Cabernet Sauvignon and Shiraz.

The experiment is being paid for by the hospital's own charity rather than the National Health Service.

STUDY: TV and Obesity

JOURNAL: Pediatrics 2002;109:1028-1035

AUTHORS: Dr. Barbara A. Dennison

ABSTRACT: As America's kids continue to pack on the pounds, a team of doctors recommends a simple step that parents can take to lower their preschooler's risk of obesity: removing the TV from the child's bedroom.

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COMMENTARY: Their study of low-income youngsters aged 1 to 5 years found that kids with TV sets in their bedrooms watched nearly 5 hours more TV and videos a week and were more likely to be overweight than their peers without bedroom TV sets regardless of the parents' education. Black and Hispanic children tended to watch more television than their white peers did, according to the report in Pediatrics.

The findings support other research showing that body mass index (BMI), a measure of weight in relation to height, tends to increase in tandem with the number of hours spent in front of the TV set among older children. However, few studies have examined whether TV-watching was associated with excess weight among younger kids.

Parents should not put TVs in their child's bedroom and (should) limit their child's TV viewing to 1 to 2 hours a day.

In the United States, nearly one quarter of low-income children younger than 5 years are overweight. Excess weight in childhood raises the risk for adult obesity and increases the chances of developing heart disease, type 2 diabetes and other chronic diseases.

Therefore, future studies should investigate whether watching fewer hours of television or removing TV sets from kids' bedrooms can help lower the rate of childhood obesity, the researchers suggest. In an interview, Dennison added that future studies should also investigate the relationship between overweight and having a TV in the bedroom among children from wealthier families.

The American Academy of Pediatrics recommends that parents limit children's total media time to 1 to 2 hours of quality programming per day, remove television sets from children's bedrooms and discourage television viewing for children younger than 2 years. Parents are also encouraged to view television programs with children and discuss the content.

The study findings are based on a survey of more than 2,700 low-income parents with preschool-aged children. Nearly 40% of kids had a TV set in their bedroom, raising their risk of overweight by nearly one third.

Black children watched nearly 18 hours of TV a week, Hispanic youngsters watched about 15 hours and white children watched nearly 13 hours of television each week. About 43% of Hispanic children were overweight, compared with 35% of black children and 33% of white children.

Because most children watch TV by age 2, educational efforts about limiting child TV/video viewing and keeping the TV out of the child's bedroom need to begin before then.

STUDY: New research suggests not all calories equal

JOURNAL: American Dietetic Association

AUTHORS: Donald Layman

ABSTRACT: For years diet doctors have criticized Americans for yo-yo dieting. But looking at the protein advice given by nutrition specialists over the past year or two, it seems instead that it’s the experts who’ve been bouncing back and forth with no clear advice for confused consumers.

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COMMENTARY: At one time or another, protein, carbohydrates and fats have all been vilified. These days, when you sit down to a meal it seems as if you’re facing a traitor in every bite.

A prime example of recommendation flip-flopping is the experts’ advice on protein. Back in the 1960s, Americans were told they would be healthy if they ate lots of meat. But over the next two decades, health experts began to promote high-carbohydrate diets and to warn Americans against eating too much protein.

When the low-carbohydrate, high-protein Atkins’ diet first came out 30 years ago, and again after its recent resurgence in popularity, mainstream experts came out strongly against it: protein — along with fat — is what is killing Americans, they intoned.

In fact, in 2000, the American Heart Association published several statements critiquing the regimen. The association insisted that there was no evidence showing that high-protein meals could lead to weight loss and they might even hurt the dieter’s kidneys and rob strength from the bones.

A year later, the heart association backed off these statements a bit and simply argued that weight loss seen by those following the protein gurus was simply “fluid loss.” And still they warned against deviations from the USDA’s Food Pyramid.

NEW PROTEIN RANGES

But the tide seems to be turning yet again.

The latest nutrition guidelines seem to reflect confusion even among the experts. No longer are there hard and fast numbers for the percentages of major food groups. Now protein can range from 10 percent to 35 percent of daily intake. At the annual meeting of the American Dietetic Association, nutritionists basically admitted that they really don’t know how much protein Americans need.

And several new studies have shown that diets that have moderately high levels of protein can lead to weight loss that targets fat and spares muscle, said Donald Layman, a professor in the department of food science and human nutrition at the University of Illinois, Urbana-Champaign.

While all low-calorie diets lead to weight loss, recent research has shown that not all calories are created equal, Layman said at the meeting. For example, one new study looked at two groups of dieters: one with a high-protein regimen —125 grams of protein and 171 grams of carbs — and one with a high-carbohydrate regimen — 68 grams of protein and 246 grams of carbs. Both groups were also required to exercise.

At the end of four months, people who ate more protein lost more weight — 22 pounds versus 15 pounds. Further, people on the high-protein diet had lost more fat and less muscle than the group on the high-carb diet.

Another important finding: higher levels of protein may also help dieters stick with their plans.

Studies have shown that protein, more than carbohydrates or fat, leads to feelings of fullness and satiety, said Richard Mattes, a professor of foods and nutrition at Purdue University.

People given a high-protein breakfast feel full longer than those who eat a carbohydrate-rich breakfast, Mattes said.

Mattes also cautioned that the form of protein consumed makes a difference. Solid protein is satisfying. Protein in liquid form is not.

DIETING RECOMMENDATIONS

Ultimately, the percentage of protein you need will depend on whether you are dieting or not, said Cathy Nonas, of the New York Obesity Research Center in New York City. “If you’re on a 1,200 calorie a day diet and want to lose weight and you’re only eating 10 percent protein, you’re not getting enough protein to support lean tissue. Even 20 percent isn’t enough to support lean tissue. Studies have shown that you need to get at least 76 grams of protein, so that means you have to go to the upper ranges of the protein recommendations for a 1,200 calorie diet.”

But Nonas and the other experts stopped short of recommending the very high levels of protein suggested by eating plans like the Atkins’ diet because these plans so drastically cut carbohydrates — the initial phase of the Atkins’ diet limits carbohydrates to 20 grams a day. T

That’s because carbohydrates are the major source of fiber in the diet. Just cutting carbohydrates back to 50 percent of your diet would be enough, Nonas said, and that would still allow for enough carbs to be within the range recommended by the ADA.

You can increase lean protein and decrease carbohydrates and still have a really healthy mix.

Remember to start your day with protein and have some form of protein at every meal.