We’ve always known that our minds have a powerful effect on what goes on inside our bodies. One example is the placebo effect. In any given trial, the placebo effect can be as high as 30%: some people who get the placebo get the real result. This is mind over body. The Hallelujah Diet was built on the understanding that our body, mind, and spirit are all connected together. What affects one affects the others. So the mind can have a powerful effect on the body. And a couple of research studies have shown this to be remarkably true.
What Harvard Researchers Found
In 2019, a study was published to answer this simple question: Do optimistic people live longer?
The answer was a resounding yes.
The article was published in the Proceedings of the National Academy of Sciences. Lead researcher Lewina O. Lee, along with colleagues from Boston University and Harvard’s T.H. Chan School of Public Health, tracked two large cohorts, the Nurses’ Health Study and men from the Veterans Affairs Normative Aging Study. They measured levels of optimism at the start of the study and then followed participants for up to 30 years to see who lived the longest.
Here’s what they found:
Women in the highest optimism quartile lived about 15% longer than those in the lowest quartile. Men showed similar results. And when the researchers looked at who made it to age 85, which they called “exceptional longevity,” the most optimistic participants had 1.5 to 1.7 times the odds of reaching that milestone compared to the most pessimistic ones. That’s a 50 to 70% advantage just from mindset.
And it’s even more interesting because the results remained significant even after controlling for health behaviors like exercise, diet, and smoking, and taking into account socioeconomic status, social integration, depression, and other health conditions.
It wasn’t just that optimistic people happened to make better lifestyle choices, although they often do. And it wasn’t that they just had better circumstances. The optimism itself was an independent factor for promoting longevity.
Of course, the optimists always expected this result. And the pessimists assumed there were errors in the study’s methods. They suspect that the results aren’t valid.
Well fine. Here is some more data from a different study.
More Research Shows Optimism Boosts Health
In 2017, a companion study was published in the American Journal of Epidemiology. Some of the same Harvard researchers working with the Nurses’ Health Study tracked 70,000 women over six years. They found that women in the highest optimism quartile had a 29% lower risk of dying from any cause compared to the least optimistic women, for every major cause of death: heart disease, stroke, cancer, respiratory disease, and infection.
Now some of the women are in both of these study publications,, so it’s not a completely independent result here. This result shows that it’s not just about living longer, but also having less disease along the way, for a better quality of life.
Think about that for a moment. One mindset trait — something you can actually work on and (more on that below) — was associated with dramatically lower risk of death from the leading killers in our society.
Why Does Optimism Protect Health?
Researchers have proposed several mechanisms. Optimistic people tend to get over their stressors more quickly. This helps keep cortisol and inflammatory markers lower over time. A lady recently told me, “Pain is inevitable, but suffering is optional.” True, indeed. Suffering is always an inside job that we do to ourselves, right?
“Pain is inevitable, but suffering is optional.”
Chronic stress and the inflammation it drives are linked to accelerated aging, heart disease, diabetes, and cancer — so anything that dampens that stress response has real biological consequences.
A second mechanism is that optimists also tend to engage in more health-promoting behaviors. They’re more likely to exercise, eat well, get adequate sleep, and follow through on medical care. Their optimism creates a virtuous cycle: a positive outlook drives healthy habits, which in turn reinforce it. They help create a better future for themselves by their beliefs.
The 2019 PNAS study showed it wasn’t just the behaviors that optimistic people adopt, it was optimism itself that helped shape the body’s stress and immune responses.
The Bible Says: A Joyful Heart is Good Medicine
What is remarkable is that none of this would have surprised the ancient writers of Scripture. The Bible speaks repeatedly about the life-giving power of a joyful, trusting, hope-filled heart — and the health consequences of its opposite.
Proverbs 17:22 puts it plainly: a joyful heart is good medicine (ESV). The Hebrew word used there for “medicine” (geha) refers to healing and cure. Solomon wasn’t speaking metaphorically. He was making a physiological claim that the heart’s emotional and spiritual state has a direct bearing on the body’s health.
Proverbs 12:25 adds: “Anxiety in a man’s heart weighs him down, but a good word makes him glad.” (ESV) And in Philippians 4:6–7, Paul instructs believers: “do not be anxious about anything, but in everything by prayer and supplication with thanksgiving let your requests be made known to God. And the peace of God, which surpasses all understanding, will guard your hearts and your minds in Christ Jesus.” (ESV) Peter also exhorts us in 1 Peter 5:7 “…casting all your care upon Him, for He cares for you.” (ESV)
We were not made to carry anxiety, but God wants us to turn to Him, to make our requests known to Him, and He will give us His peace, trusting Him, knowing that He will take care of us, no matter what happens. And this is powerful healing and comfort for our body, soul, and mind.
The Good News: Optimism Is a Skill
Here’s what I find encouraging about this: The researchers specifically noted that optimism isn’t a fixed personality trait you’re born with or without. It’s something you can learn, practice, and get better at over time. In short, I’m optimistic that you’ll become an optimist, too.
So what does that look like practically?
Reframe challenges as temporary. Optimists tend to see setbacks as specific and short-term rather than permanent and pervasive. When something goes wrong, practice asking yourself: “Is this really going to matter in a year?” I recently read Scott Adams’ book on “Reframe Your Brain.” I found some really good reframes that now help me look at potentially bad situations in a much better light.
Practice gratitude deliberately. There’s solid research showing that a regular gratitude practice — even just writing down three things you’re thankful for each day — measurably shifts your outlook over time.
Limit your intake of negative media. This one is simple but powerful. What you feed your mind shapes your baseline emotional state. Be intentional about it. Philippians 4:8 says, “Finally, brothers, whatever is true, whatever is honorable, whatever is just, whatever is pure, whatever is lovely, whatever is commendable, if there is any excellence, if there is anything worthy of praise, think about these things.” (ESV)
Surround yourself with encouragers. The people around you influence your outlook more than most of us realize. People say you will become like the five people closest to you. If they are really negative, watch out! Seek out relationships that build you up.
Ground your hope in Jesus Christ. For me, as well as for many of you, faith in Jesus Christ is our deepest source of optimism. Our lives have meaning and purpose in light of eternity. With the Apostle Paul, we say, “our suffering is but for a moment.” We have faith that Jesus will bring us home one day.
The Takeaway
You know that what you eat, how you exercise, and how well you sleep all matter for your health and longevity. This research is a reminder that how you think matters very much as well. So get rid of the stinking thinking.
Optimism isn’t a luxury or a personality quirk. It’s a biological force that affects your immune system, your stress hormones, your heart, and even how many years you get to enjoy on this earth. Tending to your mindset is just as important as tending to your diet.
If you’re struggling with being consistent with your diet, maybe you need to upgrade your mindset first. Take a look at that list above and see what steps you can take today to become more optimistic.
Sources:
Lee LO et al., PNAS, 2019. DOI: 10.1073/pnas.1900712116 |
Kim ES et al., American Journal of Epidemiology, 2017. DOI: 10.1093/aje/kww182
