Wednesday, August 13, 2008
The Pill Makes Women Pick Bad MatesBirth-control pills could screw up a woman's ability to sniff out a compatible mate, a new study finds.
While several factors can send a woman swooning, including big brains and brawn, body odor can be critical in the final decision, the researchers say. That's because beneath a woman's flowery fragrance or a guy's musk the body sends out aromatic molecules that indicate genetic compatibility.
Major histocompatibility complex (MHC) genes are involved in immune response and other functions, and the best mates are those that have different MHC smells than you. The new study reveals, however, that when women are on the pill they prefer guys with matching MHC odors.
MHC genes churn out substances that tell the body whether a cell is a native or an invader. When individuals with different MHC genes mate, their offspring's immune systems can recognize a broader range of foreign cells, making them more fit.
Past studies have suggested couples with dissimilar MHC genes are more satisfied and more likely to be faithful to a mate. And the opposite is also true with matchng-MHC couples showing less satisfaction and more wandering eyes.
"Not only could MHC-similarity in couples lead to fertility problems," said lead researcher Stewart Craig Roberts, an evolutionary psychologist at the University of Newcastle in England, "but it could ultimately lead to the breakdown of relationships when women stop using the contraceptive pill, as odor perception plays a significant role in maintaining attraction to partners."
Sexy scents
The study involved about 100 women, aged 18 to 35, who chose which of six male body-odor samples they preferred. They were tested at the start of the study when none of the participants were taking contraceptive pills and three months later after 40 of the women had started taking the pill more than two months prior.
For the non-pill users, results didn't show a significant preference for similar or dissimilar MHC odors. When women started taking birth control, their odor preferences changed. These women were much more likely than non-pill users to prefer MHC-similar odors.
"The results showed that the preferences of women who began using the contraceptive pill shifted towards men with genetically similar odors," Roberts said.
Pregnant state
Based on the work by Claus Wedekind, a University of Lausanne researcher who preformed similar studies in the 1990s, Roberts suggests a likely reason for the pill's effect on a woman's odor preferences. The pill puts a woman's body into a hormonally pregnant state (the reason she doesn’t ovulate), and during that time there would be no reason to seek out a mate.
"When women are pregnant there's no selection pressure, evolutionarily speaking, for having a preference for genetically dissimilar odors," Roberts said. "And if there is any pressure at all it would be towards relatives, who would be more genetically similar, because the relatives would help those individuals rear the baby."
So the pill puts a woman's body into a post-mating state, even though she might be still in the game.
"The pill is in effect mirroring a natural shift but at an inappropriate time,” Roberts told LiveScience.
The results are detailed in the current issue of the journal Proceedings of the Royal Society B: Biological Sciences.
Labels: Research
Friday, August 01, 2008
Doctors may have found a way to destroy HIVHOUSTON -- There is real hope that what’s happening in a Houston lab might lead to a cure for HIV.
“We have found an innovative way to kill the virus by finding this small region of HIV that is unchangeable,” Dr. Sudhir Paul of the University of Texas Medical School at Houston said.
Dr. Paul and Dr. Miguel Escobar aren’t talking about just suppressing HIV – they’re talking about destroying it permanently by arming the immune system with a new weapon lab tests have shown to be effective.
Ford Stuart has been HIV positive for 15 years. He’s on a powerful drug cocktail that keeps the disease in check.
“I’m on four different medications. Three of them are brand new, and it’s the first time that I’ve ever been non-detectible,” Stuart said. “I’m down to about – just for the HIV – about nine pills per day, five in the morning and four at night.”
But Stuart knows HIV mutates, and eventually it will learn how to outsmart his medications.
“The virus is truly complex and has many tricks up its sleeve,” Paul said.
But Dr. Paul thinks he’s cracked a code.
“We’ve discovered the weak spot of HIV,” he said.
Paul and his team have zeroed in on a section of a key protein in HIV’s structure that does not mutate.
“The virus needs at least one constant region, and that is the essence of calling it the Achilles heel,” Paul said.
That Achilles heel is the doctors’ way in. They take advantage of it with something called an abzyme.
It’s naturally produced by people, like lupus patients. When they applied that abzyme to the HIV virus, it permanently disarmed it.
“What we already have in our hand are the abzymes that we could be infusing into the human subjects with HIV infection, essentially to move the virus,” Paul said.
Basically, their idea could be used to control the disease for people who already have it and prevent infection for those at risk.
The theory has held up in lab and animal testing. The next step is human trials.
Meanwhile, every day in Houston, three people are diagnosed with HIV.
The doctors still need funding to launch human trials. In the world of HIV research, that’s often where things fall apart.
“Clinical trials are very expensive,” Paul said.
“That is the worry of the researcher. This is what nightmares are made of – that after 30 years of work, you find it doesn’t work,” Paul said.
But so far, it is working.
“This is the holy grail of HIV research, to develop a preventative vaccine,” Paul said.
“If we can get the viral loads down to a manageable level, that will preclude the need for these conventional drugs,” Escobar said.
Still, even if everything goes well, it’s at least five years before the research could help people with HIV.
The doctors know people like Ford Stuart are waiting.
“There are so many people struggling with the disease because it affects not only your body, but also your psyche, how you perceive yourself,” he said.
If nothing else, the research is promising for the tens of millions waiting for a cure.
Wednesday, February 06, 2008
2-cup coffee habit may double miscarriage risk
Drinking a couple of cups of coffee a day has long been considered safe during pregnancy, but a new study finds that even this modest amount of caffeine could double a woman’s risk of miscarriage.
Doctors are split on what this means for pregnant women, with some advising avoiding caffeine altogether and others saying buzz-inducing beverages are still safe in moderation.
Previous studies have linked caffeine to an increased risk of miscarriage, but they have focused on higher doses and the connection has been controversial, with some experts arguing that the research didn't account for morning sickness. The nausea and vomiting of morning sickness, caused by elevated hormones, is generally a sign of a reduced risk of miscarriage — and also can lead women to stop drinking their usual coffee or other caffeinated drinks. The concern was that the cutback in caffeine among these women could make it appear caffeine was associated with miscarriage
To get to the bottom of this puzzle, a team led by Dr. De-Kun Li, a researcher at Kaiser Permanente in Oakland, Calif., conducted one of the first studies to take into account morning sickness. They concluded that a daily habit of drinking 200 milligrams of caffeine — the amount typically found in just two cups of coffee — significantly increases the risk of miscarriage.
“If women become pregnant or are actively planning to become pregnant they should probably think about stopping drinking caffeine, at least during the first trimester when most miscarriages occur,” Li said.
“If they really have to drink, they should probably limit it to one cup of coffee per day,” he added.
Coffee, tea and soda pose same risks
The source of caffeine — whether from coffee, tea or sodas — didn't make a difference. But one thing to take into consideration is that a cup of coffee can have varying amounts of caffeine depending on how it is brewed, with some brands containing more of the addictive chemical than others. A tall brewed coffee from Starbucks, for instance, packs 270 mg of caffeine. A tall latte from the chain, however, contains 75 mg.
In the study, published in Monday’s issue of the American Journal of Obstetrics and Gynecology, Li's team interviewed 1,063 women in the San Francisco area who became pregnant between 1996 and 1998 about their caffeine intake. While 164 of the women drank 200 mg of caffeine or more daily, 635 consumed some caffeine but less than 200 mg. The remaining 264 women said they didn’t consume any caffeine.
Overall, 172 of the women suffered a miscarriage. The risk of a miscarriage was more than double in women who consumed 200 mg or more of caffeine, with 25 percent suffering a miscarriage compared to just 12 percent of women who didn't consume caffeine. The low-caffeine drinkers also appeared to have an elevated risk of miscarriage, but this trend wasn't statistically significant, meaning the researchers could not rule out that it was merely due to chance.
2-cup cutoff point
Li said the 200 mg limit can be considered a cutoff point where the miscarriage risk starts to emerge because the median consumption of the high caffeine intake group was 301 mg per day. This means half of these women were drinking less than 301 mg daily, so heavy drinkers were probably not skewing the results.
To determine the impact of morning sickness on the results, Li's team looked separately at women who experienced nausea and vomiting and those who did not. The miscarriage risk remained in both groups as long as their daily caffeine intake rose above 200 mg. In addition, the researchers looked at women who reduced their caffeine consumption during their pregnancy and those that didn’t and found that the miscarriage risk still remained in those consuming 200 mg or more of caffeine per day.
The increased risk remained even after adjusting for other factors that could up the chances of a miscarriage, such as age, previous miscarriage, smoking and alcohol consumption.
Although it's not known for certain how caffeine might trigger a miscarriage, one theory is that it restricts blood flow to the placenta, which could have a detrimental effect on the developing fetus, Li said.
Overall though, caffeine is not a major cause of miscarriage, which occurs in up to 20 percent of known pregnancies. More than 60 percent of these faulty pregnancies are due to chromosomal defects in the fetus that are beyond the mother's control.
Doctors split
Doctors on the frontlines are divided on the risks of caffeine. Dr. Tracy Flanagan, an obstetrician/gynecologist and director of women's health for Northern California at Kaiser Permanente, said that based on the study findings, she will be more emphatic about advising her pregnant patients to cut back on coffee and other caffeinated beverages.
Flanagan said that along with other prenatal advice, such as taking folic acid supplements, no alcohol and no smoking, she would add limiting caffeine intake to no more than the amount in one cup of coffee per day or to cut it out entirely.
But Dr. Katharine O'Connell, a gynecologist at Columbia University, remains unconvinced. She said the study would not be enough to change her advice to patients and doubted it would overturn current recommendations from the American College of Obstetricians and Gynecologists that moderate caffeine intake during pregnancy is safe (ACOG said it does not comment on individual studies).
“I would tell my patients that two cups of coffee per day should be fine,” O'Connell said.
She noted however that the findings were intriguing because previous studies that have linked caffeine to an increased risk of miscarriage involved much higher amounts — the equivalent to several cups of coffee per day. But the current study suggests the risks begin at a lower amount, so this may warrant further investigation, she said.
Too early for alarm
It's too early to sound the alarm though, according to O'Connell. Larger studies that confirm the miscarriage risk would be necessary before these relatively low amounts of caffeine are considered unhealthy, she said.
Without a final word on the matter, moms-to-be are likely to hear conflicting advice from their doctors and simply decide on their own whether lattes are worth even the slightest chance of a risk.
Tammy Plotkin-Oren, a coffee-lover and mother of three daughters in San Francisco, said giving up java while pregnant is doable and she should know. After her first attempt at pregnancy seven years ago ended in miscarriage, Plotkin-Oren, 35, went cold turkey during subsequent pregnancies.
Although there's no way to know if her 3 to 4 cups of coffee habit per day played a role in the miscarriage, she said she decided to eliminate her intake during her next three pregnancies as part of her overall health plan and each one resulted in a successful birth.
Plotkin-Oren missed the social aspect of meeting friends for coffee and developed headaches from caffeine withdrawal, but overall she found it easy to kick the habit. “It wasn't that hard because I was committed to doing everything I could to ensure a successful pregnancy,” she said.
Monday, February 04, 2008
Your Body Can Burn Fat on Its OwnWouldn’t you just love it if your body decided to burn fat and calories on its own?
It can:
1. Exercise in short, intense bursts (interval training) for effective fat burning after exercise.
2. Increase the amount of resistance/strength/weight training you do, to build more lean muscle. Muscle is ‘metabolically active’ and burns more calories than other body tissue even when you’re not moving.
And of course, for best results:
3. Chill on the amount of food you are eating.
Technically:
1. Our bodies are built to survive, so when you exercise for long periods of time (often and consistently) your body thinks it needs to hold on to fat for energy. Doing short (12-15 minute), intense exercise sessions builds strength and burns calories, but not fat, so it “feels safe” using fat stores for energy after exercise.
2. Resistance training (using extra weight) helps build lean muscle mass (and strong bones), and muscle burns more calories than fat.
3. If you are obsessing over things like fat grams and not eating a nutritious diet, your body will reserve energy (store fat) to survive.
Realistically:
1. Varying your exercise is the most effective and efficient way to stay lean and healthy. You must do some longer exercise to build cardiovascular endurance, burn lots of calories, and yes, even burn fat during exercise - your body will not click in to “save” mode unless you exercise for long periods of time, regularly and often.
2. You must do resistance training in order to build muscle and strong bones.
3. Nobody wants to exercise more - and we don’t want to train our bodies to need more exercise to stay fit. So exercise efficiently – two short, very intense (relative to your level of fitness) training sessions weekly, like a 15-minute fast run/walk or fast cycling sprint intervals, and two moderately long, moderately intense sessions (30-45 minutes) of strong walking, cycling, or yoga, with one long day (60-90 minutes) of a moderately paced walk/hike. That’s a great five-day/week training schedule.
4. Instead of adding more days to your workout schedule, add a weighted vest to your training. I have said this before, but this is the most efficient way that I know of to build muscle while burning calories. For more information, go to http://www.walkvest.com/.
5. Eat moderately - stop counting fat grams and calories and look at how much food is on your plate! And eat more nutritiously by eating foods that are natural and unprocessed.
Thursday, January 31, 2008
Wear Red Day promotes heart health for women
Friday is National Wear Red Day and it kicks off American Heart Month.
National Wear Red Day started in 2004 because less than 20 percent of women in America knew what their No. 1 killer was Heart disease is the No. 1 killer in men and women, but the push toward women's heart health came from the common misconception that heart disease is a man's disease. One in three women has cardiovascular disease, and every minute one woman dies as a result of heart disease.
Everyone can support the fight against heart disease in women by wearing red. It's a simple, powerful way to raise awareness of heart disease and stroke.
Monday, January 28, 2008
Guide to Herbal Supplements
It is estimated that 18 million adults use herbs in some form, and the sale of these products only continues to increase.
Herbal supplements, which come from plants that have medicinal properties, claim to cure, treat, or prevent disease. But when an herbal supplement is billed as “natural” on the label, that doesn’t ensure its efficacy, purity, or safety. Although there are proven health benefits for some herbal products, potentially harmful effects exist for others.
Claims about herbal products are often based on folklore or testimonial instead of scientific studies. It is import to read reliable information and search out unbiased sources of research, when available. Because herbal supplements are not standardized, the same herb can be found in different products in varying amounts. This can lead to toxic levels that may cause harmful reactions in the body. Do not assume that natural means safe.
To reduce health risks when choosing and using herbal supplements:
- Always tell your doctor if you are taking herbs. Herbs can interact with other medications causing serious side effects.
- Do not self-treat serious medical conditions with medicinal herbs.
- Do not take herbal supplements if you are pregnant or breastfeeding. There is no way to determine what level of herbs may harm a fetus or nursing infant.
- Do not give herbal products to children under 3 years of age. Always check with your child’s pediatrician first.
- Only purchase herbal supplements that display an expiration (or use-by) date, as well as a lot or batch number.
- The herbal supplement should state which part of the plant was used to make the product, such as root, leaf, or blossom.
- If a blend of ingredients is used in the herbal supplement, the label should list the individual ingredients as well as the amount of each.
- Although not required, the supplement should indicate the type of solvent used when processing the herb.
Check for certification symbols, such as:
- A United States Pharmacopeia (USP) symbol verifies that the product contains the stated ingredients in amounts and strength, is pure, meets limits for contaminants, and disintegrates quickly.
- National Science Foundation International verifies products for content and label accuracy, purity, contaminants, and manufacturing processes.
- ConsumerLab.com independently tests supplements for purity and active ingredients. A supplement company can pay to have its product evaluated, use the seal of approval, and be listed on the website.
Be a smart shopper! Use the following resources to research beyond the product information provided in stores:
- National Library of Medicine National Center for Complementary and Alternative Medicine
- The Health Professional’s Guide to Popular Dietary Supplements, Allison Sarubin Fragakis, MS, RD, American Dietetic Association, 2003
- The ABC Clinical Guide to Herbs, Blumenthal M, Brinckmann J, Wollschlaegar B, American Botanical Council, 2002
Commonly Used Herbal Supplements
Black Cohosh is a member of the buttercup family. Some evidence indicates that as an alternative to hormone replacement therapy, it may help manage menopausal symptoms like hot flashes, irritability, and anxiety. It is also used to relieve premenstrual cramping and pain, but more research is needed. However, no drug interactions have been reported. Women who are pregnant (it can stimulate uterine contractions), lactating, or at high risk for breast cancer (it may make breast cancer more likely to spread) should not use Black Cohosh.
Research on chamomile tea supports claims that it reduces muscle spasms in the gastro-intestinal tract, indigestion, and menstrual cramps. Individuals who are allergic to ragweed or pollen may have an allergic reaction to chamomile.
Drinking cranberry juice (about 10 ounces daily) may reduce the incidence of urinary tract infections. However, more research is needed to determine the efficacy of cranberry extract supplements. There is no evidence that cranberry juice or pills can treat an existing urinary tract infection, so consult your healthcare provider for treatment.
Echinacea is also known as the purple coneflower. Studies suggest Echinacea enhances the immune system and may reduce upper respiratory infections, but it should be taken intermittently (not permanently) and only when ill. Individuals with autoimmune disorders should avoid Echinacea (it may offset the effects of drugs that suppress the immune system), and those with asthma or sensitivity to grass or pollen may experience allergic reaction.
Feverfew is effective in treating migraine headaches, possibly by inhibiting inflammatory mediators. It is most effective when taken daily as a preventive measure. Choose tablets, which only contain a small amount of the active ingredients. Chewing the leaves can cause mouth sores as well as allergic reactions. Feverfew reacts adversely with anticoagulant and anti-platelet medications.
Garlic supplements (2-5 grams daily) have been shown to reduce cholesterol and blood pressure, as well as fight infection and reduce platelet aggregation. Garlic may cause gastrointestinal discomfort in some and increased bleeding. Therefore, avoid garlic seven days prior to surgery; if you take blood-thinning drugs, talk to your physician first.
Studies support the use of ginger (250 mg, 2-4 times per day) to alleviate motion sickness. No toxic effects have been reported, but ginger may interact with anticoagulant drugs. Pregnant and nursing women should consult their physicians.
Ginkgo Biloba improves blood flow in areas of decreased circulation and may help with memory loss that is due to decreased blood flow. Several studies suggest that ginkgo may slow the progression of dementia, particularly in Alzheimer’s disease. However, not all studies report improvement—it does not improve memory and concentration in healthy individuals. It may also be used for diabetic neuropathy and peripheral vascular diseases. Since ginkgo acts as a blood thinner, taking it with other blood-thinning agents could increase one’s risk for excessive bleeding and even stroke.
Ginseng is the most frequently purchased herb in the United States. There are three different species of ginseng: American, Asian, and Siberian. Each has 20 or more active compounds in varying amounts. Marketing claims boast improved exercise performance, energy, and cognitive function, mood elevation, diabetes control, increased immunity, heart health, and cancer prevention. However, there is not much reliable research or evidence to support any of these claims. Ginseng may also decrease the efficacy of warfarin (coumadin) medication by reversing the drug’s effects.
Kava Kava lacks controlled studies to back claims of inducing a deep, restful sleep and relieving insomnia and nervousness. More data is needed about safe usage (since it may cause liver toxicity) but it shouldn’t be used for more than three months. Kava Kava may affect motor reflexes (so use caution when driving or operating machinery), compound the effects of substances that depress the central nervous system, and bring on tremors, muscle spasm, and decrease the effectiveness of Parkinson’s medication.
St John’s Wart (SJW) may improve symptoms of mild to moderate depression, according to clinical trials conducted in Europe. But its effects on patients with major depression are contradictory and much more research is needed. There is no evidence that SJW elevates mood or improves emotional well-being in individuals without clinical depression. Combining herbal and prescription antidepressants could lead to adverse side effects. Consult your physician for usage.
Valerian may improve sleep quality without morning drowsiness, but more studies are needed to see if it reduces anxiety and stress. Valerian is not for extended use. It may add to the effects of sedatives, alcohol, and sleeping pills and cause dangerous interactions.
"On your way to a happier, healthier you!"
Labels: Herbal Supplements
Thursday, January 24, 2008
High Mercury Levels Are Found in Tuna SushiPotentially dangerous mercury levels in fish and sushi were found in a wide range of places -- including randomly selected restaurants and Publix.
Young women and children may want to reconsider whether they want to eat fresh tuna.
Samples of fish and sushi purchased last fall in 26 U.S. cities, including Miami, contained mercury levels at or above levels considered dangerous to women of child-bearing age, young children and other at-risk groups.
Oceana, a Washington-based ocean conservation group, hired an independent laboratory to evaluate 94 random samples of tuna, swordfish, tilapia and mackerel collected from supermarkets and sushi restaurants.
Oceana released its findings Wednesday. Most alarming were the levels of mercury found in tuna, which the U.S. Food and Drug Administration and Environmental Protection Agency previously considered safe for women and children to eat in moderation.
RISING CONCERNS
One-third of the tuna sushi samples tested contained enough mercury that the FDA could order it removed from the market.
Concerns over mercury in fish have risen in recent years as studies suggested it can interfere with a child's developing nervous system.
The levels of mercury found in Oceana's study puts tuna on par with some of the fish the FDA and EPA have told women of child-bearing age and children never to eat: shark, swordfish, king mackerel and tilefish.
''Tuna is one of the most commonly eaten fish,'' said Jackie Savitz, senior campaign director for Oceana, who lives part time in Miami.
``It's important that people get this information so they can make informed choices about what they're eating and feeding their kids.''
WARNING SIGNS
But until that happens, Oceana wants to see supermarkets place warning signs up on its seafood counters alerting customers to the current government recommendations.
Although Publix has a pamphlet available to customers explaining the issue, Savitz doesn't believe that gets consumers' attention. The study found that six of the seven seafood counter clerks at Publix stores across the Southeast were unable to explain the government seafood eating guidelines to customers.
Publix spokeswoman Brous argues that because the findings are so detailed, a pamphlet is more effective.
''Our job is to educate our shoppers,'' Brous said. ``Giving them more information is better.''
Miami Herald staff writer Fred Tasker contributed to this report, which was supplemented with information from the New York Times Service.
BY ELAINE WALKER of the MIAMI HERALD
Labels: Food Safety, Mercury