By: Rachael Rettner, Senior Writer
Published: 11/11/2013 05:07 PM EST on LiveScience
Taking vitamin E or beta-carotene does not appear to reduce the risk of cancer or cardiovascular disease, according to a new review from a government-appointed panel of experts.
However, there isn't enough evidence to say whether other vitamins or minerals (such as vitamin D, calcium and selenium) or multivitamins reduce the risk of these two conditions, according to the review from the U.S. Preventive Services Task Force.
Although the effect of vitamins is unclear, some studies do suggest that a healthy diet reduces the risk of cancer and heart disease, the researchers said. [10 Do's and Don'ts to Reduce Your Risk of Cancer]
"In the absence of clear evidence about the impact of most vitamins and multivitamins on cardiovascular disease and cancer, health care professionals should counsel their patients to eat a healthy, well-balanced diet that is rich in nutrients," said Dr. Michael LeFevre, co-chair of the task force. Doctors should also consider the latest research as well as their patients' preferences when discussing vitamin supplements, LeFevre said.
The recommendations from the review apply to healthy adults without nutritional deficiencies, but do not apply to women who are pregnant or plan to become pregnant. (It is recommended that these women take folic acid supplements.)
The task force reviewed about 30 studies looking at the effects of vitamins and multivitamins on cancer and cardiovascular disease.
Many studies on individual vitamins showed no benefit, but there were too few studies on any single vitamin to make a definitive conclusion about the substances' benefits or risks, the task force said.
But there were two exceptions: vitamin E and beta-carotene. For Vitamin E, studies showed that taking the supplement did not prevent cancer or heart disease, but also was not harmful, overall. For beta-carotene, taking the supplement was linked with an increased the risk of lung cancer among smokers.
Although some research suggests that multivitamins may reduce the risk of cancer, these studies tended to involve specific groups of people, and more research is needed before the findings can be applied to the general population, the task force said.
The new review is an update to the task force's 2003 recommendations. At that time, there was not enough evidence to assess the benefits or harms of most vitamins, but taking beta-carotene for the prevention of cancer or heart disease was not recommended.
The Academy of Nutrition and Dietetics says that, although multivitamins may be useful in helping some people meet recommended levels of certain nutrients, there is no evidence that the supplements are effective at preventing chronic diseases.
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Getting To Sleep Late
<strong>We always hear you should spend some time away from screens before bed -- but if you <em>have</em> to work late one night, is it better to spend time unwinding, even if it means staying up a bit later, or is it better to just go right to bed?</strong> I am a big proponent of consistent <em>wake</em> times. Bed times, in my opinion, are much less important; if a patient is consistent with their wake time and routines, bed times usually take care of themselves. Plus, deemphasizing when an individual goes to bed often helps remove the performance anxiety we associate with insomnia. For me, this one is a no brainer: Unwind first, if you feel like you need it. If you are someone who can go to sleep without that down time, knock yourself out. --W. Christopher Winter, M.D., medical director of the Martha Jefferson Hospital Sleep Medicine Center in Charlottesville, Va.
<strong>If you've decided to indulge in one thing while out for a meal, which should it be: the bread basket or dessert?</strong> I think it's better to share a dessert (of course be the last to taste so there's only a bite or two left). The bread basket is a trigger point for the whole meal. Once people make the choice to have the bread they are subconsciously choosing to let the whole meal go and they ultimately end up eating dessert too. If you save it for dessert (eating clean the whole meal before and skipping the bread), you'll save a ton of calories. --Heather Bauer, R.D., CDN, founder of bestowed.com and HuffPost blogger
Walking In Heels
<strong>More steps are almost always better -- but is it still worth walking that extra bit if you're wearing heels?</strong> No! I do not subscribe to walking in heels for exercise being a good idea. High heels shift your body weight to the ball of your feet and misalign your whole skeleton. Exercise in this body position makes you very prone to injury to knees, hips, back and feet. Exercising later in more appropriate shoes is ideal. Everyone wants to get in as much physical activity as possible, but putting yourself at risk for injury and trauma isn't smart. Exercise should be done with the goal of strengthening your body, not causing harm. Sneakers are always best for physical activity. --Jackie Sutera, D.P.M., podiatrist in New York City
Tackling Your To-Do List
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Rushing At The Gym
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Fat Vs. Protein
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Early Morning Workout?
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<strong>We've heard it's not great to nosh late at night -- but if you haven't had a chance to eat dinner all evening, is it better to eat late or go to bed starving?</strong> Eat something but more <em>snack</em> size rather than meal size. Having a gnawing hunger or eating too much food both will lead to poor sleep quality. Try 1/4 cup tuna salad (homemade/healthy mayo), six multi-seed crackers and cut fresh veggies. --Dawn Jackson Blatner, R.D., author of The Flexitarian Diet
Bad Breakfast Choices
<strong>Ideally we'd be prepared -- but if you're stuck in an all-morning meeting and the only food choice is a pastry, is it better to eat it or skip breakfast?</strong> SKIP IT. There is nothing actually filling about a pastry -- no fiber, no water -- so it wouldn't help my hunger. In fact, many times eating something high in sugar like this will lead to an energy crash, so I wouldn't be full and it makes me tired. No thank you! (I have apples and almonds at my office for situations like this.) ----Dawn Jackson Blatner, R.D., author of The Flexitarian Diet
Should You Google?
<strong>Pouding headache? A weird pain in your side? When you have an unusual system, is it a good idea to Google your symptoms to be a better informed patient, or does searching the internet for a diagnosis only put you at risk for cyberchondria?</strong> We all know the saying that a little knowledge is a dangerous thing, and that's certainly true when you think you know more than you do! Medical information emphasizes the dire, with good reason. It is the most dire explanation for any given set of symptoms that most needs to be found, and addressed. That by no means indicates it is the most likely, however. But while a little knowledge is a potentially dangerous thing, total ignorance is even more so. Doctors are human, and fallible. Mea culpa! There have been times I have come faster to a correct diagnosis, or considered something important, because my patient came to me armed with a Google search, and asked me: 'what about ______?' So, yes -- Google your symptoms. But do so reasonably, and humbly. Reasonably means prioritize credible sites- not those devoted to conspiracy theories. One very good portal is healthfinder.gov. Humbly means to remember that an hour of Internet surfing is NOT a substitute for four years of medical school and several more of residency training. So, use a Google search to generate good questions- but not to cultivate a passion for any given answer. There have been times I have struggled mightily to disabuse a patient of a false conviction based on a wayward Internet search, and we have both suffered for it. Don't let that be you. Informed is empowered, and is much better than uninformed. But misinformed and unwilling to recognize it may be the worst of all. Google accordingly! --David Katz, M.D., founding director of Yale University's Prevention Research Center
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