热量 (rèliàng) means "heat" or "thermal energy," referring to the measurable quantity of warmth or energy. It is also used in nutrition to mean "calories," depending on context.
这块蛋糕的热量太高了,我还是少吃一点吧。
Zhè kuài dàngāo de rèliàng tài gāo le, wǒ háishì shǎo chī yīdiǎn ba.
This piece of cake is too high in calories; I'd better eat a little less.
冬天身体需要更多的热量来保持体温。
Dōngtiān shēntǐ xūyào gèng duō de rèliàng lái bǎochí tǐwēn.
In winter, the body needs more calories to maintain body temperature.
她每天都会计算食物的热量,控制饮食。
Tā měi tiān dōu huì jìsuàn shíwù de rèliàng, kòngzhì yǐnshí.
She calculates the calories in her food every day to control her diet.