The best ways of looking after your health can differ dramatically through the decades, while problems can arise at certain periods in your life, such as during pregnancy.
In a bid to boost your fitness, whatever your age, check out when you could face certain health risks and when you should seek guidance or treatment.
AGEING SKIN: TEENS
Skin changes are the most visible signs of ageing, and the rate at which it happens can be affected by factors such as sun, diet and smoking.
Clair Rose, head of cosmetics at Dr Lewinn's, says: "Sun damage is the worst contributor to ageing, and sadly most sun damage is done before the age of 18, so the sooner you start a skincare regime, the better.
"When I meet women for consultations, I always ask what their daughter uses too. Hydration is the best armour against lines and wrinkles. I always refer to a plum and a prune - and point out that the difference is that a prune is just as dehydrated plum.
"Using a good moisturiser from a young age is key, although it's never too late to start caring for the skin."
LASER EYE SURGERY: EARLY 20S
Every year around 100,000 people in the UK have laser eye surgery, which can free them from the inconvenience of prescription glasses and contact lenses.
Chidambara Pillai, founder and medical director of Advanced Visioncare, a laser eye clinic, advises: "Although the Royal College of Ophthalmology says that the ideal age for laser vision correction is 19, we believe that a patient should be 21 as the documented evidence is that people's vision continues to change under this age.
"The prescription needs to be stable in order for laser vision correction to be performed.
"We will perform surgery on patients below the age of 21, however we require two to three years' worth of prescriptions from their optician."
"Provided surgery is done properly and the eyes remain stable for a year after laser treatment, laser eye surgery is for life and does not regress," he adds.
"However, some people undergo laser eye surgery again later in life because even though their distance vision remains good, people more often then not start to require reading glasses at this stage.
"As long as the eyes are healthy and the patient has no cataracts, we can treat this problem later."
FERTILITY: EARLY 30S
While increasing numbers of women are having babies after the age of 40, a woman's egg count starts to significantly decline at 30 years old.
In your 30s, fertility should be on your health radar, says Dr Marilyn Glenville, a women's health expert and nutritionist.
"Even if you haven't yet considered having a baby, maybe it's not the right time or you haven't met the right partner, you can't start safeguarding your reproductive health early enough," she advises.
"Certainly in your early 30s, it's very important.
"The amount of eggs you have is set and can't be altered because the store was established in your body since before you were born, but you can take control over the quality of those eggs.
"So make sure that you're doing everything you can to keep yourself as healthy and fertile as possible. Perhaps the most important thing you can do to protect fertility is to eat a healthy diet.
"Then think about toxins coming in. Quit smoking as it makes eggs age faster and can increase the risk of miscarriage, and drink less alcohol as this can affect your fertility.
"Consider taking a good fertility-boosting multivitamin and mineral that contains good levels of zinc (the most important mineral for fertility), folic acid, antioxidants such as selenium, beta-carotene and vitamin E (to keep your eggs as healthy as possible), plus other nutrients such as manganese and the B vitamins.
According to researchers, a specially formulated fertility multivitamin and mineral supplement could double your chances of getting pregnant and help you produce better quality eggs.
BUNIONS: EARLY 40S
A bunion is a bony deformity of the joint at the base of the big toe, known as the metatarsophalangeal joint. Celebrities such as Victoria Beckham, Gwyneth Paltrow and Tilda Swinton have all reportedly suffered from the painful problem.
Dave Wain, podiatrist and managing director at Carnation Footcare, advises bunions can affect anyone at any age, but are commonly found in those aged 40-plus.
"They can be hereditary, but they can be caused or made worse by ill-fitting shoes, such as high heels which throw the weight on to the balls of the feet and the toes."
Even if the problem is genetic, aggravation of the problem can be prevented by wearing properly fitting shoes, he says, and exercising the feet and big toes with stretches.
In a small number of extreme cases, surgery may be necessary for bunions, but age will play a part.
Surgery may not be advisable for young people because of the increased risk of a bunion returning while the bones are still growing. Surgery can make toes less flexible, which can impact on athletes or dancers.
"Most bunions can be relieved by wearing a bunion pad or shield which fits to the contour of the joint," Wain suggests.
LEG CIRCULATION: EARLY 50S
Varicose veins and spider veins may occur at any age but usually they become present between the ages of 18 and 35, and peak between 50 and 60.
"Thread veins, tired aching legs and varicose veins are common problems, especially among more mature women," says Kimby Osborne, a training director at Activa Healthcare.
"If left untreated, these can lead to more serious problems such as varicose veins, swollen ankles or even leg ulcers."
Poor circulation contributes to spider veins, thread veins, tired, aching legs and swollen ankles, she explains.
She suggests compression therapy, such as compression hosiery and support socks, which may alleviate aching legs and prevent more serious problems from occurring.
HEART DISEASE: EARLY 50S
Coronary heart disease is the UK's biggest killer, causing around 82,000 deaths each year. About one in five men and one in eight women die from the disease.
Dr Wendy Denning, a general practitioner, says heart disease is the number one killer of women in the country and kills three times more women than breast cancer.
"During our menstruation years, we are relatively well protected from it, but once we hit 51 (the average age women go into the menopause), we need to start looking after our hearts so that we don't become another statistic in our `60s, `70s and `80s."
She recommends annual health check-ups from age 50, particularly if you have a family history of heart disease, which will look at blood pressure, cholesterol, weight, dietary patterns, exercise habits, stress levels and smoking.
Doctors will also carry out a C-reactive protein (CRP) test, a general marker for inflammation and infection, as well as a HbA1c test, which measures the percentage of haemoglobin molecules in red blood cells that have glucose attached to them.
The CRP level can be improved by taking a fish oil or lycopene supplement.
One of the most common problems in this age group is constipation and bowel problems.
Cassandra Barns, nutritionist at The Nutri Centre, says: "This can be due to less effective movement of food through the gut, which can be down to diet or inactivity.
"Try eating high-fibre cereal foods and ensuring a good intake of fruit and vegetables. It's also important to drink plenty of fluid.
"Fluid intake is important, as the risk of dehydration can be higher in older people because their kidneys don't function as efficiently as those of younger people."
Nutritious snacks, such as oatcakes, toast with sardines or pilchards, vegetable soup or a bean salad, in between meals can boost nutrient intake.