If there's one place where it's a good idea to come clean, it's the doctor's office. Patients with an ache, a symptom or a bad habit like smoking do no one any good if they keep it to themselves. Yet there's one time doctors are often less than forthcoming: when they have to tell patients they need to lose weight.

Researchers at the Mayo Clinic in Rochester, Minn., recently released the results of a survey of more than 2,500 obese patients who went to their doctor for a regular checkup over the course of a year. The investigators found that the charts of only 1 in 5 of those people listed them as obese. What isn't on the charts is probably not communicated between doctor and patient either, and that means trouble. Those in the study who got the diagnosis were more than twice as likely to have developed a weight-management plan with their doctor than were the other obese patients.

"If you don't have a plan, you're not going to lose weight," says the study's author, preventive-medicine specialist Dr. Warren Thompson, whose research was published in August's Mayo Clinic Proceedings.

Obesity, of course, means a higher risk of heart disease, diabetes, hospitalization and early death, so how come doctors are so lax about putting the scarlet O on the chart? Sometimes, Thompson says, doctors perceive that a patient isn't motivated to change, so they just don't bother. Other times, the patient's likely embarrassment silences the physician, or time constraints get in the way as more immediately pressing health concerns get dealt with.

Discussing weight becomes even more complicated with children. According to a 2005 study in the journal Pediatrics, doctors diagnosed obesity less than 1% of the time among 2-to-18-year-olds—a figure far below the one-third of young Americans struggling with weight.

Dr. Mark Jacobson, an adolescent-medicine specialist with the American Academy of Pediatrics, explains that parents may feel guilty about having an overweight kid because they know it's partly hereditary and because they feel it's their responsibility to control their youngster's exercise levels and diet. Parents also worry about a child's developing eating disorders if weight becomes an issue, so they say nothing at all.

"I've had a patient whose mother whispered the letters w-e-i-g-h-t to me, with her hand over her mouth so the child couldn't see. I could tell it was something they had thought about and didn't want to bring up with the child," says Jacobson. Still, he insists that doctors must discuss the topic. One way to do so gently, he says, is to avoid the word obese and instead say the child has a weight problem. Doctors may also tell kids that their weight is a couple of years ahead of their age. Then, Jacobson says, he focuses the discussion more on the behaviors that could help improve the situation—like watching less TV and playing outside more—instead of concentrating principally on shape.

"You don't want to make people feel embarrassed and not want to come back to you. You want them to get treated," he says. Jacobson stresses that every pediatrician should determine a child's body-mass index (BMI)—a figure arrived at by factoring weight and height to produce a two-digit number that roughly diagnoses obesity. BMI is an imperfect metric, in part because it does a poor job of taking body type and muscle mass into consideration, meaning that a stocky person with low body fat can be labeled obese. But as a starting point, BMI helps.

None of this absolves patients or parents from stepping forward and bringing up weight on their own. But whoever raises the topic, it's important for patients and doctors alike to remember that modest amounts of weight loss can disproportionately benefit overall health, even if the loss doesn't feel or look like much. That fact may be the best reason for everyone to show a little courage and say what needs to be said — even if it hurts a bit.

有个地方你去了最好是老实交代，这地方就是医生诊疗室。头疼脑热，大症小状，抽烟等坏毛病医生都问得清清楚楚，闷着不说出来可一点儿好处都没有。然而，医生也有犹豫的时候：当他们不得不告诉病人，该减肥了。

明尼苏达州梅奥诊所的研究人员最近公布的一个项调查结果显示：接受医生定期检查一年的2500多名肥胖患者中，仅有1/5的人登记为肥胖症。没有在列的人员很可能也没有进行医患双方的交流。这就意味着不正常。参与研究的病例中，那些得出诊断结论的病人与医生合作控制体重的概率是那些没有登记的肥胖病患的两倍多。

“如果没有减肥计划，体重一般不会降低，”该研究报告的作者，预防医学专家沃伦汤普森博士说，他的研究结果发表在梅奥诊所的公报中。

当然，肥胖意味着更接近心脏病、糖尿病、住院和提早死亡。那为什么医生不及时在诊断书上把肥胖这项勾出来呢？有时候，汤普森说，医生觉得某个患者主动减肥的热情不高，他们也就不庸人自扰了。其他时候，医生顾忌到患者可能会觉得尴尬，还有时候是其他更迫切的健康问题阻挠了肥胖问题的提出和解决。

青少年肥胖问题更为复杂。根据儿科杂志2005年的调查研究，在2到18岁的青少年中，只有不到1%的人被医生诊断为肥胖症，而约1/3的美国青年遭受肥胖困扰。

美国儿科学会的青少年医学专家马克·雅各布森博士解释说，如果医生说出实情，父母们可能会为拥有一个过重的孩子感到内疚，因为父母会觉得肥胖症部分是遗传问题，而且他们觉得自己要对控制子女的活动量和饮食负责。如果肥胖被提上日程，父母还会担心孩子们在成长时期饮食是不是不规律，所以医生们都绝口不提。

“有个患者的母亲低声做出‘肥胖’两字的口型，还用手挡着她的嘴，怕她孩子看到。我可以看出父母们也在思考这个问题，但是他们不想带给孩子这种困扰，” 雅各布森说。但是他仍然坚持讨论这个话题。有一个婉转一点的办法，他说，就是避免“肥胖”这个字眼，可以说孩子有体重问题。医生还可以对孩子们说他们的体重比他们的年龄长得快了两年。然后，雅各布森将讨论的重点更多地放到了什么样的习惯能改变这种局面—像少看电视，多进行户外活动—而不是就体型问题抓着不放。“你也不想让患者感到尴尬从此再也不来你这里了。你希望的是他们得到治疗，”他说。雅各布森强调每一个儿科医生都应该确定孩子的身体重量指数（BMI）--一组通过身高除以体重得出的数据，能大致诊断是否患有肥胖症。BMI是个不完美的公式，部分是因为它没有将体重与肌肉很好地结合考虑，也就是说，一个矮小结实没有肥肉的人可能测出来是肥胖。但是作为初诊，BMI是有帮助的。

这些对于患者和其父母勇敢说出并停止发胖本身并没有帮助。但是无论谁提出问题来，病患和医生都要记得，即使有时候看不出也感觉不出减了多少，适当减肥能或多或少地对全面健康有帮助。这个事实可能是鼓励每个人表现出一点勇气来说出肥胖困扰---即使有点尴尬。