鄭遠峰

Once you become an adult，you typically reach your full height. But your height can change with age，and its no myth — you shrink with time.

People usually lose about a centimeter in height every 10years after age 40，according to Medline Plus，and that pace of height loss speeds up after age 70. Overall，you can lose between 1 to 3 inches in height as you age，per Medline Plus.

While age-related height loss is normal，there are times when its a sign of an underlying health condition.

Why do you get shorter as you age？

On a macro level，you get shorter as you age due to changes in the bones，muscles and joints.“There are a few different things going on here，”Dr.Angela Catic，a geriatrician and associate professor in the Huffington Center on Aging at Baylor College of Medicine，tells Yahoo Life. One，she says，is that the discs between the vertebrae in your spine lose fluid as you get older.“They become dehydrated and，with that，they lose height — and you lose a bit of height，”she says.

Abdominal muscles also tend to weaken over time，which can create a stooped posture，causing you to appear shorter，Catic says.

In women，menopause can speed up bone loss“due to the loss of the protective effects of estrogen on bones，”Dr.

Arashdeep Litt，an internal medicine physician with Spectrum Health，tellsYahooLife.That，too，cancauseyoutogetshorter.

But height loss can also be due to osteoporosis，a bone disease that develops when bone mineral density and bone mass decreases，or when the quality or structure of bone changes，Litt says. That can decrease your bone strength and increase your risk of fractures，according to the National Institutes of Health（NIH）.

How to tell the difference between normal height loss and signs of osteoporosis

So，how can you know whats behind your shrinking size？ Your doctor will suspect osteoporosis if you have an overall height loss of 1.5 inches or more，Litt says.“This much height loss is a sign of osteoporosis and warrants a bone density test，”she says.

The test can tell how strong your bones are and will determine if you have osteoporosis，as well as your risk of fractures in the future.

How to prevent height loss

Again，some height loss is normal. But Catic says you can lower your risk of height loss by doing the following：

Exercise regularly.

Lift weights（this，along with regular exercise，stresses your bones and makes them stronger）.

Eat a diet rich in calcium and vitamin D to support bone health.

Avoid smoking，excessive alcohol use and excessive caffeine intake — all of which are risk factors for osteoporosis.

人在成年之時，通常身高會達到頂點。但是你的身高會隨著年齡而改變，年紀大了就會變矮，這并不是什么秘密。

醫(yī)學網(wǎng)站 Medline Plus 稱，在 40 歲后每過十年人的身高通常會縮水1厘米左右，70歲后身高縮水速度會加快。總體來看，人在年老后身高會縮水1到3英寸（2.5到7.6厘米）。

盡管人老了變矮是正常現(xiàn)象，但是有時候也預示著潛在的健康問題。

為什么人老了會變矮？

從宏觀層面來看，人在衰老時會因為骨骼、肌肉和關(guān)節(jié)的變化而變矮。美國貝勒醫(yī)學院赫芬頓衰老研究中心的老年病學專家、副教授安吉拉·卡蒂克博士告訴雅虎生活頻道： “有幾種不同情況。”一種情況是，年紀大了以后，脊柱椎間盤所含的液體會減少。她指出： “脊柱椎間盤脫水后會變短，從而讓你變矮?！?/p>

卡蒂克說，另一種情況是，腹部肌肉隨著時間流逝會衰弱，從而會導致駝背，讓你看起來更矮。

健康機構(gòu)Spectrum Health的內(nèi)科醫(yī)生艾拉什迪普·利特博士告訴雅虎生活頻道，女性絕經(jīng)會加速骨質(zhì)流失，因為“雌性激素對骨骼的保護作用減弱了”，這也會令其變矮。

但是利特指出，變矮也可能是由骨質(zhì)疏松導致的，骨質(zhì)疏松指的是骨密度和骨量下降，或骨骼質(zhì)量或結(jié)構(gòu)發(fā)生改變。美國國立衛(wèi)生研究院稱，這會降低骨骼強度，增加骨折風險。

如何區(qū)分正常的身高縮水和骨質(zhì)疏松癥

那么，怎么知道是什么原因?qū)е伦约鹤儼哪?？利特說，如果你身高縮水總量超過1.5英寸（3.8厘米），你的醫(yī)生就會懷疑你得了骨質(zhì)疏松癥。她指出： “身高縮水這么多是骨質(zhì)疏松的跡象，需要進行骨密度測試?！?/p>

這種測試可以測出你的骨強度，并確定你是否有骨質(zhì)疏松癥，以及未來發(fā)生骨折的風險。

如何預防身高縮水

年紀大了變矮一些是正常的。但是卡蒂克指出，你可以通過做以下幾件事來降低身高縮水風險：

定期鍛煉。

舉重（舉重和定期鍛煉都能強健骨骼）。

攝入有助于骨骼健康的富含鈣和維生素D的膳食。

避免吸煙、酗酒和過量攝入咖啡因，這些都是導致骨質(zhì)疏松的風險因素。