Dietary fats are important because they are the ones that produce  energy for the body. Fats should be monitored since excessive fats  can be risky for your health.
Age last birthday: One method of insurance rating which rates people a their age as of their last birthday, with such rating held until the next birthday. If your policy is approved at your current age (prior to your next birthday), you will be rated at your current age (as opposed to age nearest birthday).
trees of unknown age; His age is 20 years. 2. a period of human life, measured by years from birth, usually marked by a certain stage or degree of mental or physical development and involving legal responsibility and capacity: the age of discretion; the age of consent; The state raised the drinking age from 18 to 21 years.