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Planning for the future often feels like trying to navigate the unknown. With Project BigLife, you gain a clearer view, backed by data and scientific models. Using interactive calculators, the tool provides insights into your life expectancy, health risks, and aging.
Life is full of decisions, and many of them are guided by a sense of time—how much we have, how long it will last, and what we can do to extend it. Certain tools exist that can help us get a clearer picture of how much time we may have left, based on the choices we make.
One of Project BigLife’s standout tools is the Life Expectancy Calculator, which estimates how long you might live based on lifestyle factors like diet, exercise, and smoking habits. This calculator is appropriate for people of all ages, though we will go over a specialized calculator designed for much older people next. The Life Expectancy calculator doesn’t just offer a generic number based on a quiz. It accounts for individual health habits, providing a personalized estimate of longevity. This can be crucial when planning for retirement, assessing future healthcare needs, or deciding on major life events. Knowing that choices made today—what you eat, how active you are—directly affect your future lifespan can inspire meaningful changes.
For example, the tool reveals that the life expectancy of a 20-year-old varies by as much as 18 years depending on healthy living behaviors. Such insights are more than just interesting—they’re powerful motivators for adopting healthier lifestyles.
While the Life Expectancy Calculator gives insight into the length of life, the RESPECT tool (Risk Evaluation for Support: Predictions for Elder-life in the Community Tool) is designed to help individuals and families plan for the final stages. It assesses frailty and helps predict how much time a person might have left, offering critical information for those transitioning into assisted living or considering end-of-life care options. RESPECT provides not just numbers, but guidance on how to manage the practical realities of aging.
The Life Expectancy Calculator used by Project BigLife is built upon a foundation of robust research, particularly the study, "Seven More Years: The Impact of Smoking, Alcohol, Diet, Physical Activity, and Stress on Health and Life Expectancy in Ontario," conducted by the Institute for Clinical Evaluative Sciences (ICES) and Public Health Ontario (PHO). This report meticulously explores how various lifestyle behaviors—such as smoking, physical activity, and diet—affect life expectancy, helping shape the data-driven predictions used by the Life Expectancy Calculator.
The model underlying this calculator is built using data from large-scale population surveys, such as the Canadian Community Health Survey (CCHS). For the Seven More Years study, responses from over 78,000 Ontarians aged 20 and older, collected between 2001 and 2005, were analyzed. The researchers followed these participants for nearly a decade (until 2010), tracking health outcomes and mortality rates. This vast dataset allowed them to create a multivariable risk model capable of predicting mortality based on behaviors and risk exposures such as smoking, alcohol consumption, physical inactivity, and diet.
Download the study below:
The study focused on five critical behavioral risks:
For each of these risks, the researchers calculated how much each behavior affects life expectancy. For instance, heavy smokers were found to live approximately 11.5 years less than non-smokers. Meanwhile, those exposed to all five unhealthy behaviors (heavy smoking, poor diet, physical inactivity, high stress, and excessive alcohol consumption) experienced a 20-year reduction in life expectancy.
To estimate life expectancy, the researchers used a combination of data on mortality risk and Health Utilities Index (HUI) scores, which measure the health-related quality of life across six domains such as mobility and cognition. This allowed them to assess not only how long people might live but also the quality of those years. This exploration of healthspan is one of the best documented studies of a large population set that clearly and definitively shows what you can do to live healthier for longer. By comparing life expectancy for those who exhibit healthy versus unhealthy behaviors, the calculator gives a detailed picture of how lifestyle changes might add years to your life—or conversely, shorten it.
One of the most compelling findings from the study is the potential for gains in life expectancy through even modest changes in behavior. For example, the researchers found that if every Ontarian improved just their worst health behavior (e.g., if a smoker quit smoking or an inactive person became moderately active), the average life expectancy could increase by up to 3.7 years. In total, eliminating all five risk factors could add as much as 7.5 years to life expectancy and 9.8 years to health-adjusted life expectancy (years lived in good health).
Project BigLife goes beyond longevity predictions with a range of health risk calculators focused on conditions such as cardiovascular disease, dementia, and chronic kidney disease. These tools evaluate personal health habits and medical histories to estimate the likelihood of developing certain conditions. For instance, the cardiovascular disease calculator considers your diet, physical activity, and smoking status to give a detailed risk profile for heart attacks or strokes
These calculators empower users to take proactive steps. A higher risk for heart disease or dementia doesn’t have to be an inevitable outcome. With this data in hand, users can adjust their habits and make health-conscious choices that reduce their risks.
There's a shift in thinking that happens when you use this tool. Health no longer feels like something you can only manage by visiting the doctor once a year or taking the right medication. Instead, the Life Expectancy Calculator shows you that your day-to-day actions, no matter how small, are directly tied to your future.
If you’ve been ignoring those five extra pounds or postponing your plans to start exercising, the calculator can act as a wake-up call. By turning lifestyle factors into a tangible estimate, it empowers people to take ownership of their health in a new way. The question of "How long will I live?" becomes less about fate and more about choice.
In a sense, the Life Expectancy Calculator doesn’t just give you an answer—it invites you to rewrite that answer through your actions. Each meal, each workout, each skipped cigarette becomes a step toward shaping the future you want to see. It's not just about the years added to your life, but the quality of those years, and knowing that many of these factors are in your hands is both powerful and liberating.