You don't eat the same food you would have eaten a century ago, you don't breathe the same air. You don't have the same lifestyle, work-rest balance or sleep patterns. You touch and interact daily with completely different materials than people did 100 years ago. So the risks to your health that you are facing today are not necessarily the same risks that the medical canon described based on your anatomy and physiology, which were formed not just a century but millenia ago. So you have to go beyond the canon to assess and mitigate risks to your personal health. You also expect to live decades longer than people who lived a century ago. Moreover, you expect those decades to be much healthier too. So your assessment of risk-reward balance of preventive measures must also be different. Your tolerance to risk-reward ratio of the preventive measures you employ to increase the odds of those healthy extra decades of your life might also be higher. The risks to your health today often hide in plain sight, they continue to evolve. Therefore, you need to tackle the actual risks you personally encounter every day, in your real life. You must recognize them correctly and assign due value to their magnitude. You cannot rely only on some hypothetical, averaged, theoretical risks decribed in the textbooks.