Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:
Ebola Spreads to Large City in Congo
The Ebola outbreak in Congo has spread to the major eastern city of Butembo, and there are concerns about vaccine supplies.
The appearance of the deadly disease in the city of more than 1 million adds to the already difficult task of containing the second-largest Ebola outbreak in history, the Associated Press reported.
The number of new cases is rising rapidly in the city's eastern suburbs and outlying, isolated districts, according to the medical charity Medecins Sans Frontieres.
Health experts wonder if the supply of an experimental Ebola vaccine will be adequate to cope with the outbreak that was declared on Aug. 1, the AP reported.
To date, there have been 423 confirmed cases, including 225 confirmed deaths, Congo's health ministry said Thursday.
So far, more than 41,000 people have been vaccinated. Vaccine maker Merck has a stockpile of 300,000 doses, and preparing them takes months, the AP reported.
"We are extremely concerned about the size of the vaccine stockpile," Dr. Peter Salama, emergencies director, World Health Organization, said in an interview with the STAT media outlet this week.
He said 300,000 doses is not sufficient as Ebola outbreaks in cities become more common, the AP reported.
Whole Grain-Rules for School Lunches Rolled Back by Trump Administration
Foods made mostly of refined grains and low-fat chocolate milk will once again be allowed in the U.S. school lunch program, as the Trump administration changes standards introduced under the Obama administration.
Under the previous rules, only whole grains could be served and only fat-free milk could be flavored, the Associated Press reported.
The Trump administration is also scrapping a final target for limiting sodium, but schools will still have to meet reduced sodium standards.
Only half the grains served will have to be whole grains, the U.S. Department of Agriculture said Thursday. Products affected include noodles, tortillas, biscuits and grits, the AP reported.
The whole grain-only rule was too difficult for some districts to meet, according to the School Nutrition Association, which represents local cafeteria operators and food companies.
But the American Heart Association urged schools to "stay the course" and meet the stricter standards that started taking effect in 2012, and the Center for Science in the Public Interest said reversing the whole-grain requirement makes no sense because most schools were already in compliance, the AP reported.
The school lunch program, which provides low-cost or free lunches, served about 30 million children last year.
Study That Targeted "Joy of Cooking" Retracted by Journal
A study that targeted the "Joy of Cooking" has been retracted because of problems with the data, the journal Annals of Internal Medicine says.
The 2009 study claimed that recipes in updated editions of the cookbook were changed to have more calories and larger portions, the Associated Press reported.
The study analyzed the cookbook's recipes as part of an investigation into whether home cooking might be a factor in rising obesity rates.
The study co-author was Brian Wansink, who recently resigned from Cornell University after school officials said he engaged in academic misconduct, including misreporting of data, the AP reported.
Wansink's work has been widely cited and he has influenced U.S. dietary guidelines.
Several of Wansink's studies have been retracted since a blog post he wrote in 2016 led to questions about the validity of his work. Those studies include one that said people eat more when food is served in big bowls, and one that examined people's ability to estimate the calories in meals, the AP reported.
Excess Body Fat May Increase Older Women's Breast Cancer Risk: Study
Excess fat may increase older women's risk of breast cancer, even if they're not overweight or obese, according to a new study.
It included 3,460 American women, ages 50-79, who had gone through menopause. An 11-pound increase in total body fat was associated with a 35 percent increased risk of ER-positive breast cancer and a 28 percent increased risk of invasive breast cancer.
An 11-pound increase in torso fat was associated with a 56 percent increased risk of ER-positive breast cancer and a 46 percent increased risk of invasive breast cancer, CNN reported.
The study was published Dec. 6 in the journal JAMA Oncology.
"The main takeaway is that having excess body fat, even when you have a normal body mass index, is associated with an increased risk for breast cancer," said study author Dr. Andrew Dannenberg, director of cancer prevention at the Sandra and Edward Meyer Cancer Center at Weill Cornell Medicine, CNN reported.
The study highlights "the importance of research differentiating the contributions of body size, body composition, and metabolic profiles to breast cancer risk," Dr. Isabel Pimentel, Dr. Ana Elisa Lohmann and Dr. Pamela Goodwin wrote in an accompanying editorial.
They said "these observations suggest that components of metabolic health, rather than the presence of full metabolic syndrome, may contribute to breast cancer risk."