Phone numbers, PIN numbers, Social Security numbers. We know these numbers by heart, but what about the numbers that are near and dear to our heart? Most people can probably rattle off their weight and height, but ask most of us about our cholesterol levels, blood pressure or body mass index and we’re as strapped for answers as high school freshmen in calculus class.

While we may not all have ideal bodies, doctors say we should at least be shooting for ideal numbers when it comes to health and fitness. Knowing your vital stats is important, health professionals say, because these benchmarks help us keep track of our health. With that in mind, here are some of the numbers that medical professionals use for measuring health:

Heart health by the numbers

120/80: Ideally, blood pressure should be under 120 over 80. The first number, which is always higher, measures systolic pressure. That’s the force of blood pressing against the arteries when the heart pumps. The second, lower, number measures diastolic pressure, which is the blood pressure between each heart beat. Hypertension, which can lead to stroke, heart disease, kidney damage and even memory problems, is indicated when systolic pressure is higher than 120 or when diastolic pressure is higher than 80. "Both warrant treatment, so both numbers count," says Dr. Jennifer Lindstrom, a specialist in internal medicine and clinical nutrition at Albany Medical Center.

200 or Less: Most people know that high cholesterol levels have been linked to heart disease, but many people are confused about the way cholesterol levels are measured and what the different numbers mean. Here’s the breakdown. Cholesterol levels are measured in milliliters of cholesterol per deciliters of blood, and they are measured in four ways:

Total cholesterol: Ideally, should be under 200 mg/dl. However, cholesterol includes triglycerides, a component of cholesterol that relates to blood sugar, and that number should be under 150. High triglyceride levels can cause fatty deposits to build up in the liver and can lead to diabetes and heart disease.

High-density lipoprotein (HDL): Is considered good cholesterol, so higher numbers here are better — higher than 40 mg/dl for men and higher than 50 mg/dl for women. "If you have high good cholesterol, it can offset the bad," says Lindstrom.

Low-density lipoprotein (LDL): Is bad cholesterol, and it should be no higher than 160 and ideally under 100. "This is the one that’s confusing to people," says Lindstrom, explaining that the target number for each person depends on family history and personal health, and varies accordingly. "For someone with diabetes, it should be less than 100 — one group argues that it should be under 70, but that hasn’t been adopted by the Heart Association yet but at a minimum, 100 if you’re diabetic or have heart disease," she says.

The bottom line is that the math varies and each number matters. "You can’t just look at one number," says Lindstrom. "You have to look at all four."

The body beautiful

18.5 to 25: In the old-math world of beauty queens, 34-24-34 added up to the perfect figure. Medically speaking, the new math is a bit more complicated because it is based on body mass index (BMI). To calculate it, multiply your weight in pounds by 703 and divide that figure by your height, in inches squared. (If you don’t want to do the math, you’ll find a BMI calculator online at the Centers for Disease Control — http://www.CDC.gov — website.)

18.5 to 25: Is considered a healthy BMI. 25 to 30 is considered overweight; and greater than 30 is obese. According to the latest statistics, two-thirds of American adults fall into the obesity range, and childhood obesity is a growing problem too.

35 and 40: BMI is used as a screen for adiposity, or excess fat, but as visceral belly fat is considered the most dangerous, waist circumference is another measure of health. Even if you’re of normal weight, a pot belly is a health risk. As a general rule, a waist measurement of less than 35 inches for women and 40 inches for a man is considered healthy.

To get an accurate measurement, wrap the tape measure snugly around your waist just above the hips (across the belly button) and relax.

Medically, you’re better off being pear shaped than apple shaped, but as body shape is inherited, there’s not much you can do to change it short of plastic surgery. Trimming your waistline, however, reduces the associated health risks of heart disease, diabetes and certain cancers.

Less than 100: Type 2 diabetes, which is linked to obesity, is a growing health concern for many people. If your weight or family history put you in a high-risk category, it’s particularly important to have your blood sugar levels tested regularly.

Ideally, fasting blood sugar levels should be less than 100. Numbers between 100 and 126 are consistent for pre-diabetes, numbers over 126 are consistent with diabetes, but you’ll need more than this one test to confirm that diagnosis.

Age isn’t just a number

21: To avoid false positives, gynecologists now recommend that women get their first pap test at age 21, with yearly gynecological exams up to age 25. Depending on personal history and risk, gynecologists may want to see women every year or once every three years thereafter.

40: Most doctors still recommend that women get their first mammogram at 40, with annual screenings through age 50, at which point they recommend a screening mammogram every two years for women of average risk for breast cancer. Mammograms have not proven to be very effective for women 75 or older.

50: Colonoscopies are recommended for both women and men starting at age 50, earlier if there is a family history of colon cancer. Tests are generally conducted once every 10 years thereafter, unless the doctor finds polyps, in which case you may need to be tested every three to five years.

60 and up: Doctors recommend bone density screening about 10 years after the onset of menopause. Women who have had surgical menopause or who are on certain medications, such as steroids, which increase the risk for osteoporosis, however, will need to be screened at an earlier age.

"The point about all these screening tests is these are just guidelines," says Lindstrom. "People may fall outside these guidelines, depending on their personal risk and family history. That’s why it’s really important for them to talk to a doctor about it." 

The daily numbers

» 1 percent: Consume low-fat dairy products that are 1 percent fat or made from skim milk.
» 300 milligrams: To help keep your cholesterol levels low, eat fewer than 300 milligrams of cholesterol a day.
» 1,500 milligrams: Although it’s not easily done if you eat a lot of prepared or processed foods, try not to consume more than 1,500 milligrams, or 3/4 of a teaspoon, of sodium a day.
» 6 ounces: Juice is a good way to boost your fruit and vegetable intake, but it’s high in sugar. Limit yourself to one 6-ounce glass of 100 percent juice a day.
» 1: The number of alcoholic beverages a nonpregnant or nursing woman should have in a day.
» 6 to 9: Nutritionists recommend that everyone get six to nine servings of fruit and vegetables every day. That sounds like a lot, but bear in mind that one serving size fits into a cupped hand, so a large apple alone gives you just over two servings.
» 30 minutes: Adults should spend at least 30 minutes a day doing something active. To lose weight, however, you’ll need to do more than 90 minutes of exercise each day. Can’t find the time to do it? Experts say exercising in 15-minute bursts is as effective as doing it all at once. To get the most out of each workout, try to reach your target heart rate (subtract your age from 220; your target heart rate will be 65 percent to 85 percent of the sum of that calculation).
» 8 hours: Adults need at least seven hours of sleep a night, but eight hours is optimal. To get a good night’s rest, sleep in a dark, quiet room. — Albany Times Union

Weight loss equation

» Spend 5 minutes every day making my bed, I’ll have burned more than 4,000 calories in a year of bedmaking. (caloriesperhour.com)
» Jump rope for 15 minutes a day, I’ll burn about 150 to 200 calories (depending on weight) and could lose 15 pounds in a year. (caloriesperhour.com)
» Stand up on my toes 200 times while doing the dishes, I’ll have burned 36,000 calories in a year. (That’s a potential 10 and a half pounds shed.) (http://www.bhg.com/health-family/weight-loss/diets/lose-5-pounds-with- calorie-savers/)
» Spend an hour of my day standing at the computer rather than sitting, I’ll burn 36 more calories an hour. If I do this every day, I could lose almost four pounds in a year, just by standing instead of sitting. (http://www.rd.com/living-healthy/8-ways-to-burn-calories-without-notic ing/article16261.html)
» Laugh for 10 to 15 minutes, I can burn up to 50 calories. (http://www.msnbc.msn.com/id/37378884)
» Skip a glass of wine a week, I could save consuming an extra 5,200 calories in a year. (http://www.davidstuff.com/wine/calories.htm)
» Stay away from bread and butter when dining out, that’s about 200 calories. Assuming I go out once a week on average, I could lose three pounds in a year by eating everything else I usually do at a dinner out, except the bread. (http://thebodyyouwant.com/newsletter-30)
— Brianna Snyder, Albany Times Union