This month I have to renew my driver’s licence and, in so doing, share personal information about my body with bureaucrats. Hair colour: brown. Height: 178 centimetres. Weight: 59 to 68 kilograms, depending on the time of year.

Truth be told, I’ve never owned a scale and don’t weigh myself often. But I do know that when I feel sexy in short skirts and tight T-shirts, I’m at the low end of what I consider my normal weight range. And that when my belly flab hangs over my belt, I’m at the high end. When I think my body looks best in clothes, I find my naked reflection scrawny with pointy edges: a breastless Twiggy. And when I hate how my size 13 jeans fit, I love the way I look naked: a Rubenesque beauty, baby!

All this got me to wondering what my perfect body weight should be.
According to Kelly Howatson Keay, weight trainer and group fitness leader, there is—but there isn’t—a perfect body weight. “When I say ‘perfect body’ I’m thinking of reference charts and the Body Mass Index. These calculations provide an ideal weight for an imaginary male and female body, but they’re not realistic or accurate for any unique individual. For instance, people who are fit and very muscular can rate ‘obese’ on the BMI since muscle is heavier than fat,” says Keay.

Vince Ziccarelli, a registered dietician, holistic nutritionist, and founder of Nutrition Wellness Center (nutritionwellness.ca [1]), adds, “We all have different genetics, body structures, and family histories, so the best way to determine your own perfect body weight is to identify the weight at which you feel your best.”

Ziccarelli says that nine out of 10 of his clients can easily tell him how much they weigh when they have their highest energy levels, when their immune system is working well (so they don’t catch colds easily), when their stress levels are easily managed, and when they just have an overall feeling of well-being. This, he says, is how to determine your natural, genetic weight, which will be your healthiest body weight.

Based on that approach, I should be striving to maintain 63 kgs. Given that it’s winter, my “stay cozy inside and eat comfort food” season, my size 13 jeans are feeling snug and my energy is low, so I know I’m above my healthiest weight.

Keay recommends I do 20 minutes of cardio every day. “The goal for a beginner,” she says, “is to get your heart rate raised to 50 per cent of its maximal.” To determine your maximal heart rate, take your age and subtract it from 220. Then multiply that number by your desired exercise intensity. For a beginner that’s 50 per cent. After 20 minutes of exercise, check your heart rate by taking your pulse for one minute.

In my case, 220 minus 42 (my age) times 50 per cent means I should count 89 beats in those 60 seconds. I can do that just by dancing in my living room for 20 minutes. When 20 minutes no longer gets my heart really beating, I can either add five minutes to my daily exercise or dance harder to make sure I’m still working on getting back to my healthy weight.

Ziccarelli also advises eating nutrient-rich foods. “Nutrients regulate your appetite, boost your metabolism, help burn fat, prevent disease, and slow down aging.” He points out that our genetic diet, the Paleolithic diet, included 20 servings of fruit and vegetables and 50 to 100 grams of fibre each day. “Today, we eat five to 15 grams of fibre and have seen a correlation to increased digestive disorders, cardiovascular disorders, and weight management issues.”

Keay and Ziccarelli agree that it’s critical to set realistic goals and to stop comparing our bodies to anyone else’s. That’s not easy when you’re standing in line at the grocery store looking at magazines that celebrate perfect Hollywood bodies and chastise celebrities who let the world see their cellulite at the beach.

Using words from Ziccarelli, I’ve developed a checkout mantra that I’ll repeat as I unload fresh fruit, vegetables, and whole-grain foods onto the conveyor belt: “I am the best me I can be. I will strive for my goals, and I will be happy with what I achieve.”

And, to stay happy when my body is heavier than what feels healthy, I’ll just spend more time in my most natural state: naked!

At 42 years old, Donna Barker has decided that bathing suits with skirts are actually kind of cool.