(CNN) -- (CNN) -- Here's a roundup of five medical studies published this week that might give you new insights into your health, mind and body. Remember, correlation is not causation, so if a study finds a connection between two things, it doesn't mean that one causes the other.
1. Not all vitamins are good for you: Studies show that niacin does not reduce heart problems
For the past 50 years or so, some doctors thought taking high doses of niacin or vitamin B3 could help lower bad cholesterol and raise good cholesterol, thereby preventing heart attacks.
Current guidelines recommend niacin therapy as a possible way to lower the risk of heart disease and, according to a 2009 study in JAMA Internal Medicine, 700,000 Americans are prescribed niacin every month, even though scientific evidence backing up this recommendation is lacking.
A study published Wednesday in The New England Journal of Medicine found that taking niacin failed to reduce heart-disease induced deaths. It caused negative side effects such as gastrointestinal problems, excess infections, bleeding, ulcers, and an increased risk for diabetes.
The study combined the results of two separate studies, both concerned with the extended release of niacin. After looking at a large group of adults with cardiovascular disease (age 50 to 80), researchers found niacin did not reduce heart attacks and stroke rates compared to a placebo.
"There might be one excess death for every 200 people we put on niacin," said Donald Lloyd-Jones, M.D. in the editorial of the study. Lloyd-Jones is a preventive cardiologist and chairman of preventive medicine at Northwestern University Feinberg School of Medicine and Northwestern Memorial Hospital.
So, if you're popping B3 vitamin pills in hopes of lowering your cholesterol, it's time to talk to your doctor, because you may be causing yourself more harm than good.
To learn more: Time.com
2. HPV screening a better predictor for cervical cancer risk than a Pap test
Journal: Journal of National Cancer Institute
According to the CDC, 79 million Americans are infected with HPV (human papillomavirus), a sexually transmitted infection that accounts for 90% of all cervical cancers. The high rates of HPV infection make it the most common sexually transmitted infection. And while a classic Pap smear test is administered to protect women against cervical cancer, the study suggests a better way to detect it.
Current recommendations are that a woman should have a primary pap test every three years or she should get two tests at the same time, Pap smear plus HPV test, every 5 years.
A study published Friday in the Journal of the National Cancer Institute concludes that getting an HPV test every three years is "as safe, if not safer," than the current recommendations.
The study included 1 million women age 30 to 64 enrolled in Kaiser Permanente Northern California's health care system.
So, if you are one of those people who find the swabbing of your cervix uncomfortable, there may be another option.
To learn more: Pouplar Science.com
3. Stressed women + high-fat food = 11 extra pounds per year
Journal: Biological Psychiatry
It's convenient, it's cheap and it's delicious. And while we all know that the greasy burger with a side of large fries may not be the healthiest option, researchers at the Ohio State University offer yet another reason why there is little comfort in our go-to comfort foods.
Not only does stress make us crave less-healthy foods, according to research recently published in Biological Psychiatry, stress also causes women to metabolize high-fat meals more slowly. The study found this to be the case in women who experience one or more stressful events a day before eating a single high-fat meal.
It's important to note the study only questioned 58 women, who averaged 53 years old, about their previous-day stressors before giving them a high-fat meal. The meal consisted of eggs, turkey sausage, biscuits and gravy, for a total of 930 calories and 60 grams of fat. The study was designed to mimic the amount of calories and fat of a two-patty hamburger with a side of fries at a fast-food restaurant.
The results: On average, women who reported one or more stressors 24 hours prior to their meal burned 104 fewer calories than nonstressed women in seven hours after the high-fat meal -- a difference of 11 pounds in one year.
So, if you are ever wondering what's worse than a greasy meal, it may be a greasy meal after a stressful day.
To learn more: Ohio State University Wexner Medical Center
4. Being physically fit may help reduce the negative effects of sitting
Journal: Mayo Clinic Proceedings
You've heard it before. Keeping your bottom glued to a chair all day is not good for you. In fact, previous studies show that people who are physically active are not immune to the harmful effects of sitting for hours (obesity, heart disease, diabetes, certain types of cancers, etc.). But a new study released in Mayo Clinic Proceedings suggests being physically active could protect you from the risks associated with sitting for hours.
Researchers from The Cooper Institute, the University of Texas and the American Cancer Society attempted to answer the chicken and egg question of sedentary behavior: Is it the actual effect of sitting that is harmful to your health, or is it that people who spend more hours sitting tend to be less physically active?
Kerem Shuval, along with a team of colleagues, assessed the fitness levels of 1,304 men, who were asked to self-report their sedentary time. The results: Sitting time is associated with higher levels of systolic blood pressure, total cholesterol, triglycerides, body fat percentage, BMI and waist circumference. However, when controlled for fitness, the researchers found that prolonged sitting time is only significantly associated with a higher ratio of triglycerides/HDL cholesterol, and an indicator of insulin resistance.
Based on the results of the study, when taking fitness into account, sitting for prolonged periods has a less pronounced effect on developing diabetes, heart disease or excess body fat.
To learn more: Time.com
5. Do your prescription pills look different for the same prescription?
Journal: Annals of Internal Medicine
Based on the pharmacy's supply or your health insurance, your prescription drugs may be replaced with a generic form of the drug. And while generics are chemically the same thing, the FDA does not require they look the same (either color and shape) as the original drug.
A study published Monday in Annals of Internal Medicine found that when a post-heart attack patient's generic pills change in shape and color, there is a greater risk that he or she will stop taking these potentially life-saving pills.
The study collected data from 10,000 patients discharged between 2006 and 2011 after hospitalizations for heart attacks. The patients were prescribed a variety of generics, including beta blockers, cholesterol medication, etc.
The results: Researchers found the odds that the patient would discontinue use or not refill their medication increased by 34% after a change in color and 66% after a change in pill shape. A previous study, also led by researchers from Brigham and Woman's Hospital, found similar results for antiepileptic generic drugs.
So, if you are judging a pill by its shape and color, it's probably best to look past appearance and pay attention to what's inside.
To learn more: Annals of Internal Medicine