Skip Breakfast, Get Fat
Skip Breakfast, Get Fat
But more meals, if smaller, could make you thinner, study finds
FRIDAY, July 11 (HealthDayNews) — It’s a prime piece of conventional wisdom: Eat right before you go to bed and you’ll get fat.
But new research suggests that late eaters are no more likely to be overweight than anyone else. It’s what you consume the rest of the day — especially in the morning — that counts.
Americans who regularly skip breakfast are 4.5 times more likely to be fat, researchers found. But, in good news for the nibblers among us, those who eat four or more meals a day are actually on the thinner side.
“”We tend to eat because of external cues instead of internal cues — we eat until the plate’s clean. If the plate has a lot less food on it, perhaps you’ll be eating less,”" says Ruth Kava, director of nutrition with the American Council on Science and Health.
Researchers launched their study because experts don’t fully understand how eating habits — such as the timing and frequency of meals — are tied to obesity, says study co-author Yunsheng Ma, an assistant professor of epidemiology at the University of Massachusetts Medical School.
The researchers examined a national cholesterol study that took place from 1994 to 1998. A total of 499 people reported five times a year on what they ate over 24 hours.
The findings of the study appear in the current issue of the American Journal of Epidemiology.
Ma and his colleagues found people who ate more than three times a day were about half as likely to be fat as those who ate three or fewer times a day. Ma suspects the difference may have something to do with fewer spikes in blood sugar levels among the frequent eaters.
Insulin levels go up when blood sugar rises, contributing to hunger and the buildup of fat, Ma says. Similar factors may be at work among those who frequently eat breakfast or dinner away from home, he says. The study found they were 4.5 times more likely to be fat.
Someone who eats breakfast at home might settle for a small, convenient meal, Kava says. “”But if you go out, there’s all kinds of tempting things like bacon and eggs and hash browns. Maybe you tend to indulge a little bit more. You don’t have to do the work or clean up.”"
And what about the link between skipping breakfast and tipping the scales?
“”You have not broken the fast soon enough to only need a moderate amount of calories,”" says Gail Frank, a professor of nutrition at California State University at Long Beach and a spokeswoman for the American Dietetic Association. “”You are starving. How does the normal person respond? They eat, and they keep eating to compensate.”"
As for the study’s rebuttal of the time-honored belief in the fattening properties of late-night meals, Ma says more research is needed to confirm that finding.
But it makes sense, Frank says, and counteracts the “”myth”" about the hazards of midnight munching.
The body continues digesting through the night, she says, even when people are asleep and not active. “”The body doesn’t know when the lights go off,”" she says.
SOURCES: Yunsheng Ma, Ph.D., assistant professor, epidemiology, University of Massachusetts Medical School, Worcester; Ruth Kava, Ph.D, R.D. director, nutrition, American Council on Science and Health, New York City; Gail Frank, DrPH, R.D., professor, nutrition, California State University at Long Beach, and spokeswoman, American Dietetic Association; July 1, 2003, American Journal of Epidemiology
Scientists Learning More Why Aging Cells Fail to Repair Themselves
Why Aging Cells Lose Ability to Repair Themselves Study finds defect that could lead to new treatments for disease
FRIDAY, Sept. 5 (HealthWire) — A defect in the body’s self-defense mechanism against age-related genetic mutations has been identified by researchers at the University of Texas Medical Branch at Galveston.
The finding may help explain why the aging human body can’t defend itself against DNA damage in the mitochondria, the power plants that fuel the growth and activity of cells.
Finding ways to help aging cells repair their own damaged DNA could possibly lead to ways to prevent or treat cancer, Alzheimer’s disease, Parkinson’s disease and other health problems caused by genetic defects.
As cells age, they experience continuous genetic mutations, some of which are caused by the harmful byproducts of the oxygen we inhale. But the body’s repair mechanism is constantly at work fixing this DNA damage. However, this repair activity becomes less efficient as cells age.
In this study, the researchers analyzed why this DNA repair activity becomes less effective in the mitochondria as cells age. They found a biochemical “”roadblock”" that prevents much of the repair enzyme activity from reaching the site of the DNA damage in the mitochondria of aging cells.
In old cells, about half of the repair enzyme activity can’t reach the mitochondria DNA to repair it.
The study was published online this week in the Proceedings of the National Academy of Sciences.
Science Begins to Add Weight to CLA
The flurry of activity in CLA applications is being backed by a growing body of research to support the ingredient, particularly for its effects on weight loss. A review published in this month’s Journal of Nutrition supports conjugated linoleic acid’s action on weight management, concluding that it is at least in part due to regulation of glucose and fatty acid uptake and metabolism.
Conjugated linoleic acid is the common name of a group of fatty acids found in dairy products and meat. CLA isomers have been studied for their action on an impressive range of diseases, including cancer, atherosclerosis, obesity, and immune function. However as scientists begin to reveal their effects on reduction of body fat, food makers are increasingly looking at the ingredient for the valuable slimming market.
In Canada, where many of the patents for CLA are held, the dairy industry has long been studying the production of high-CLA milk. In Europe, a research centre in Ireland is studying the compound which could add significant value to its dairy industry, while in Italy, Techno Foods introduced a strawberry flavoured yoghurt naturally rich in CLA (conjugated linoleic acid) and omega-3 fatty acids this summer.
Specific CLA isomers have been shown to prevent the development of obesity in certain rodent and pig models and this has been attributed mainly to trans-10, cis-12 CLA, both in vivo and in vitro, write the University of North Carolina researchers in the review. However, CLA’s ability to modulate human obesity remains controversial because data from clinical trials using mixed isomers are conflicting.
In vitro studies by the team demonstrated that while trans-10, cis-12 CLA prevents triglyceride accumulation in human cells, cis-9, trans-11 CLA increases triglyceride content. The team concluded that the isomers’ regulation of glucose and metabolism must partly explain its mechanism on human fat.
The news is also good for supplement marketers who recently learned of research carried out by Cognis backing the long-term safety of its Tonalin CLA.
Brain Cell Growth Boosted By DHEA Supplements
‘Anti-aging’ hormone DHEA Found to Boost Brain Cell Growth August 24, 2004
Human neural stem cells, exposed in a lab dish to the steroid DHEA, exhibit a remarkable uptick in growth rates, suggesting that the hormone may play a role in helping the brain produce new cells, according to a new study published this week in the online edition of the Proceedings of the National Academy of Sciences (PNAS).
The new work, conducted by a team of scientists at the University of Wisconsin-Madison, provides some of the first direct evidence of the biological effects of DHEA on the human nervous system, according to Clive Svendsen, the study’s senior author and an authority on brain stem cells at UW-Madison’s Waisman Center.
“What we saw was that DHEA significantly increased the division of the cells,” said Svendsen, a UW-Madison professor of anatomy and neurology. “It also increased the number of neurons produced by the stem cells, prompting increased neurogenesis of cells in culture.”
DHEA or dehydroepiandrosterone is among the most abundant naturally occurring steroids in the blood of young humans, but levels decline with age and its physiological effects are poorly understood.
A synthetic form of the hormone is sold over-the-counter as a dietary supplement in the US, thought to have anti-aging properties and to offer prevention against cancer and heart disease, Alzheimer’s and other diseases. But scientists know relatively little about the drug and its basic biological effects on humans.
“We don’t know much about DHEA, but this new work adds a piece to the puzzle,” said Svendsen, who conducted the study with colleagues Masatoshi Suzuki, Lynda S. Wright, Padma Marwah and Henry A. Lardy, all of UW-Madison. “This is the first real evidence of DHEA’s effects on human neural cells.”
Svendsen and Suzuki carried out the experiments by growing human fetal neural stem cells in culture. The cells form aggregates known as ‘neurospheres,’ which were exposed to a cocktail of DHEA and growth and inhibitory factors, and observed a 29 per cent increase in new brain cells compared to cells grown in a medium with the same factors, but without DHEA.
“We saw such a pure effect of DHEA,” Svendsen said.
“It’s the only steroid we tested that had such a direct effect on stem cell growth and new neuron formation,” according to Suzuki.
The new work is important because it provides a direct window to the controversial hormone’s effects on critical human cells. Similar studies have been conducted in mice and rats, but those models have shortcomings that are difficult to address, Svendsen notes.
“There are previous studies in rats that suggest DHEA is neuroprotective, but the problem with DHEA in rats is that it is not a major metabolite in that animal so its effects may not be the same as those seen in humans,” he said. According to Lardy, metabolic products of DHEA hormone have also been shown to aid memory retention in old mice.
Despite hints from the studies in rodents that DHEA may play a role in enhancing the brain and memory, the new findings reported in the PNAS article were a surprise, he said.
“We assumed the compounds we were testing would be more active than DHEA in brain stem cells,” Lardy explains. In previous studies, Lardy, with Wisconsin biochemistry colleagues James Ntambi and Brian Fox, showed that DHEA blocked a step in fat synthesis.
“The effects of DHEA on brain stem cells is a completely new finding,” said Lardy. “The problem of whether DHEA itself is having this effect, or if there’s another metabolite of the hormone involved, still exists.”
One of the intriguing aspects of the new work, according to Svendsen, is the possibility that DHEA could have some positive effects on the adult human brain.
It is known that DHEA amounts fall progressively during aging, and reduced levels of DHEA have been reported in both adolescents and adults with major depressive disorders. And given the fact that adult humans have neural stem cells that continue to make new neurons in some parts of the brain, there is a possibility that DHEA could play a role in moderating the genesis of new brain cells.
Fish Oil Supplements Can Be Purer Than Fish
Fish Oil Supplements Can Be Purer Than Fish
University of Southern California School of Pharmacy Detects No PCBs in Fish Oil Supplements in Health Products for Americas Top Retailers.
CARSON, Calif., Jan. 9 — As more Americans eat fish to protect themselves against heart disease and other illnesses, the scientific community debates whether toxins found in fish can do more harm than good. A recent study to be published in the journal Science found that farm raised salmon contained high levels of pollutants like PCBs and pose a health risk to humans. While the debate will continue on acceptable levels of PCB consumption in fish, consumers should understand that fish oil supplements can be purer than fish and are still safe to take.
Recognizing the serious health risks associated with PCBs found in food, Leiner Health Products asked the University of Southern California School of Pharmacy (USC) to test fish oil supplements it sells to the nation’s top retailers. Using analytical procedures approved by the Environmental Protection Agency (EPA), USC randomly analyzed fish oil supplements from 18 different lots. No PCBs, dioxins or heavy metals such as lead, cadium, mercury or arsenic were detected in any of the samples.
“We used EPA’s best method (Gas Chromatography-Electron Capture Detector (GC-ECD) to test Leiner’s fish oil capsules for PCBs. This is a complex, confirmed method of analysis that has been used for over 30 years. Our analysis supports the American Heart Association’s findings of the health benefits from consuming fish oil in the form of dietary supplements. Our research proves that people can take fish oil supplements without risking their health due to possible environmental contaminant intake,” remarked Dr. Roger Clemens, Director of Analytical Research & Services, USC School of Pharmacy.
Additional samples of Leiner’s fish oil capsules were also independently evaluated by Covance Laboratories in Madison, Wisconsin. Those findings were consistent with the USC results.
Some people believe fish oil supplements contain higher concentrations of PCBs than fish but this is not true. In order to produce the purest possible fish oil, Leiner uses a process called molecular distillation to remove pollutants. This process is similar to a water purification process that traps virtually all contaminants, resulting in a “”clean”" oil.
Molecular distillation is an excellent way to rid fish oil of PCBs, other toxins and heavy metals such as mercury, lead, cadium and arsenic to below detectable levels. While it is impossible to remove 100% of all impurities, Leiner fish oil processed using molecular distillation exceeds purity standards set by California’s Proposition 65 requirements and the EPA requirements, which are much more rigorous than FDA.