Outlook: Obesity Epidemic

Ms. Farley is a freelance medical writer based in Wakefield, Rhode Island.

Higher Blood Volume in Obese Men Skews PSAs

Why are obese men more likely to bediagnosed with prostate cancer at a stagewhen it is more aggressive? Accordingto researchers, the standard blood testthat screens for prostate cancer is notas accurate for obese men because oftheir higher blood volume. By the timetheir blood levels are elevated enoughto indicate high prostate-specific antigen(PSA) levels?the standard markerfor prostate cancer?the cancer alreadyhas become advanced.

The study included approximately3400 men who took PSA tests. Resultsshowed that among obese men therisk of an aggressive cancer was twiceas high as in normal-weight men. Itis important to note that this delayeddiagnosis did not occur when obesemen were diagnosed via a digital rectalexam. Study author Stephen Freedland,MD, associate professor of urologyand pathology at the Duke UniversityProstate Center, said, "I'm not sure weshould check obese men more often,but we should have a higher [PSA] indexof suspicion of what is normal?3.4rather than 4; for really obese men, 3.2."The complete study appears in the journalBJU International.

Weight Problems Begin in Infancy

Developmental delays and asthmaare possible risks for overweightinfants, according to a recent report inPediatrics. One study included 2139infants under age 2 who were admittedto Bnai Zion Medical Center in Haifa,Israel; another study included 79 overweightinfants and 144 normal-weightinfants in a community-based assessment.Infants who were in the 85thweight-for-height percentile on 2 measurementstaken 3 months apart wereconsidered overweight.

The first study showed that infantsin the 85th to 94th percentile had fewerhospital and repeat admissions thannormal-weight babies. Infants in the95th and higher percentiles, however,had higher admission rates. In the community-based study, overweight babieswere more likely to snore and havedevelopmental delays than were normal-weight babies.

It is interesting to note that, amongthe babies in the 2 studies, only 32%of the mothers considered their babiesto be overweight. Researchers hope tostress the importance of achieving andmaintaining a normal weight in infantsand children.

Look for Even More Overweight Adults

The 30-year trend in weight for USadults indicates that most of them willbe overweight or obese by 2030, withrelated health care spending projectedto be as much as $956.9 billion, accordingto researchers at the Johns HopkinsBloomberg School of Health, the Agencyfor Healthcare Research and Quality,and the University of PennsylvaniaSchool of Medicine.

One current statistic is that 78% ofAfrican American women are overweightor obese, which supports atrend suggesting that, by 2030, 86% ofall Americans will be overweight. Itis predicted that most weight-relatedproblems will be most acute amongAfrican Americans and Mexican Americans.Researchers acknowledge thatthese statistics can be realized if currenttrends remain unchanged; thesenumbers should serve as a wake-up callonwhat could happen if individuals donot make changes.

Research Links MSG, Obesity

A University of North Carolina at ChapelHill's School of Public Health studyshows that individuals who use monosodiumglutamate (MSG) to flavor foodare more likely to be overweight orobese than those who do not use it?even if physical activity and number ofcalories are the same for both groups.

Study participants included >750Chinese men and women aged 40 to59 from rural Chinese villages. Most ofthe participants prepared their mealsat home; approximately 82% used MSGin their cooking. The participants weredivided into groups, depending on theamount of MSG they used. Those in thegroup using the most MSG were almost3 times as likely to be overweight thanpeople who do not use MSG. The study,which appears in the August issue ofObesity, is the first to link MSG andobesity.

Study Identifies Obesity Gene

Scientists studied 228 women and founda variation in the human LAMA5 genethat may be responsible for a person'sbody shape. In response to the obesityepidemic and its associated health problems,researchers feel it is important tofigure out which mechanisms controlfat storage. With the help of researchfrom a fruit fly study, scientists testedthe gene variations relating to women'sbody shape and found 2 variants: one inwomen of European American descentand the other in women of AfricanAmerican descent:

Variant 1: Associated with weightand lean mass in both ethnic groups; alsoassociated with height, total fat mass,and high-density lipoprotein (HDL) cholesterolin European American women.

Variant 2: Associated with triglycerideand HDL cholesterol levels inAfrican-American women.

Researchers used fruit fly databecause, according to team leaderMaria De Luca, PhD, of the Universityof Alabama at Birmingham, "Drosophilashare many components of fat biosynthesis,degradation, and regulation withhumans, including many of those implicatedin diabetes and obesity." The fullstudy appears in the open access journalBMC Genetics.