2023 proved to be another inspiring season of the Longevity by Design podcast, produced by InsideTracker. In 2021, InsideTracker launched the podcast to connect listeners with the leading longevity scientists to answer the key question: how can we live a healthier, longer life?
As season three comes to a close, we recap the incredible conversations of 2023. Let's dive into the seven topics on the science of healthspan discussed in 2023.
1. Women's health throughout the lifespan
Women’s biology is historically underrepresented in scientific research. Women’s health was discussed, interpreted, and celebrated during this season of Longevity by Design. From reproductive health to hormonal contraceptives, the brain-ovary connection, menopause, and more, scientists brought women’s biology to the forefront of longevity conversations. Here are a few topics within women’s health that are important to consider when it comes to women’s healthspan.
Birth control can impact women's hormone levels
Dr. Sara Gottfried shares the latest science on birth control pills, stating that they increase a woman’s risk of having low testosterone levels. Birth control pills increase levels of sex hormone-binding globulin (SHBG), which binds to testosterone and reduces the amount of free, usable testosterone in the body. Some women are more susceptible to this effect than others. Testosterone is important to monitor in women, as low levels can impact a woman’s libido, bone mineral density, muscle mass, energy levels, and more.
**As always, consult with your physician before making any medication changes.
Ovaries age more quickly than other organs
Organ function declines as people reach their 70s, 80s, and 90s. In contrast, a woman's reproductive function declines in the middle of her life. In a two-part series, Dr. Jennifer Garrison reveals that ovaries age at about 2.5 times the rate of other tissues in the body. In fact, a woman's ovaries can show signs of aging in her late 20s and early 30s.
Thyroid-stimulating hormone (TSH) levels are critical for women to track
Thyroid disorders are 5-8 times more common in women than in men. [1] Measuring and tracking thyroid-stimulating hormone (TSH) levels is essential for women, especially as they enter menopause. Dr. Jennifer Lovejoy explains that it's beneficial for women to track this hormone during their 40s and perimenopausal years because when levels are too high or too low, it can impact weight, energy, and more.
2. Managing weight can get harder as you age
It’s not just in your head; managing weight gets harder as you age. And while it’s more difficult to do, there are certain ways to counter it. During this season, two obesity specialists and a behavioral scientist discuss sustainable, healthy weight loss tactics. Here’s what they said.
Get regular exercise
Bariatric surgeon Dr. Mitch Roslin emphasizes the importance of regular exercise to support health as we age. Exercises that are particularly beneficial for weight control are zone 2 cardio and resistance training, which help maintain bone health, improve insulin resistance, and lower chronic disease risk.
Increase fiber intake
Dr. Roslin is a proponent of increasing fiber intake. Intentionally include fiber-rich foods into your daily diet, for example, salads, legumes, nuts, oats, beans, and fruit. He says, “The more fiber that goes into your food, the healthier you will be.”
When used properly, GLP-1 agonists can promote weight loss
GLP-1 agonists were a popular topic of discussion in 2023. Dr. Spencer Nadolsky shares his perspective on these medications.
For background, glucagon-like peptide-1 (GLP-1) is a hormone that controls appetite and weight by promoting feelings of fullness. Scientists have modified GLP-1 into long-acting injections used to treat type 2 diabetes and obesity. GLP-1 agonists lead to significant weight loss for individuals with obesity—on average, 15-20% of body weight.
Dr. Nadolsky shares that GLP-1 agonists can minimize cravings and the urge to overeat. He finds that his patients report feeling freedom from the impulse to overindulge. He shares optimism that GLP-1 can revolutionize obesity care as obesity rates continue to rise in the U.S.
**As always, consult with your physician before making any medication changes.
3. Insulin resistance is detrimental to metabolic health, yet is reversible
One in three adults in the United States is prediabetic, yet 80% of people don’t know that they are at risk. A precursor to prediabetes is insulin resistance, a topic that garnered attention in 2023 because insulin resistance is reversible through nutrition and lifestyle if you catch it before it develops into type 2 diabetes. Type 2 diabetes, characterized by high glucose and HbA1c levels, greatly impacts metabolic health, and when metabolic health declines, the risk of chronic disease increases. Here are tips from metabolic health scientists on reversing insulin resistance and maintaining an efficient metabolism.
Reduce dietary saturated fat
A common misconception about insulin resistance is that only carbohydrates increase blood sugar and insulin levels, making them largely responsible for insulin resistance and type 2 diabetes. Dr. Lovejoy and Dr. Roslin challenge this belief, explaining that while refined sugar increases the risk of insulin resistance, high-fat diets—especially those high in saturated fats—can also lead to insulin resistance independent of weight gain. This is because dietary fats affect 24-hour blood sugar patterns during sleep, exercise, and other activities, not just initially following meals.
4. Maintaining cognition as you age
Cognition was another top-of-mind topic in 2023. Keeping cognition strong is critical for preserving healthspan. Challenging cognitive activities build cognitive reserve, strengthening neural connections and growing new brain cells. This buffers against age-related decline, reducing dementia risk. Good cognition allows us to function well, maintain quality of life, and participate in enriching activities as we age. New tactics to maintain cognition were discussed on Longevity by Design in 2023.
Hyperbaric oxygen therapy (HBOT) can regenerate the brain
Dr. Shai Efrati and Dr. Joseph Maroon discuss Hyperbaric Oxygen Therapy (HBOT), sharing that this newer therapy has regenerative benefits for the brain. Compared to regular air, which contains 21% oxygen, HBOT can deliver 20 times more oxygen to injured organs (including the brain) and tissues via the bloodstream and promotes regeneration.
Reduce oxidative stress
Dr. Maroon shares findings from his research on oxidative stress as a primary driver in Alzheimer’s disease development rather than being a consequence of the disease. Therefore, suppressing oxidative damage with antioxidant therapies could help prevent disease progression.
Get quality sleep
Dr. Maroon notes that the glymphatic system can help prevent Alzheimer’s disease and that sleep is one of the body's most potent protective features. The glymphatic system, which removes toxins during sleep, is the brain’s waste clearance mechanism. One toxin it eliminates is amyloid beta, which accumulates in the brains of those who have Alzheimer’s disease. Studies demonstrate that people who get better sleep have a lower Alzheimer’s disease risk.
5. Regular exercise elongates healthspan
It is no secret that exercise is one of the most effective ways to optimize health. But exactly how do endurance and strength-based exercises improve health? The leading scientists discussed.
Strength-based exercise improves metabolism
Dr. Rachele Pojednic explains how contracting muscles confers metabolic benefits. When muscles contract, the body uses excess blood sugars and fats for fuel. Without exercise, surplus circulating sugar can accumulate and cause harm and raise disease risk. Similarly, excess fat from overeating can coat arteries over time and increase cholesterol levels and the risk of having a heart attack. Resistance training also builds muscle size and strength. It allows people to more easily perform daily tasks we hope to do easily as we age, like carrying children or groceries.
Aerobic exercise also improves health measures
Dr. Pojednic also discusses the connection between aerobic activity like running, swimming, and biking and cardiovascular fitness. It strengthens the heart muscle, expands blood volume to working muscles, and enhances oxygen utilization, improving endurance.
VO2max, the maximum oxygen uptake during exercise, declines naturally with age due to diminished heart rate, circulation efficiency, and artery and heart stiffening. Older muscles also cannot extract oxygen as effectively. Maintaining VO2max levels through middle age preserves independence and quality of life, enabling older adults to keep doing activities they enjoy. The endurance exercise you participate in today can help maintain VO2max levels throughout the lifespan.
6. DNA impacts health and longevity, but isn't destiny
In 2023, InsideTracker launched 10 new genetic healthspan scores. To better understand how DNA impacts our health—and what’s within our control to improve—experts in genomics weighed in.
Dr. Bartek Nogal—InsideTracker’s principal scientist discusses genetic risks and health outcomes. While certain aspects of healthspan are genetic, there are many ways to combat genetics with lifestyle habits. For example, ApoB is highly heritable, meaning a significant portion of an individual's ApoB levels are influenced by their genetic makeup. That said, eating a diet high in fiber, engaging in regular exercise, maintaining a healthy body weight, and avoiding smoking are all ways to improve ApoB and overcome genetic risk.
7. Different biological aging clocks measure different facets of aging
There are many different approaches to measuring biological age, from epigenetic clocks to blood-based clocks. This season on Longevity by Design, scientists shared their expert opinions on biological aging clocks.
Dr. Leroy Hood and Dr. Nathan Price discuss their approach to biological aging clocks: blood metabolites. Metabolic profiles reflect the functional age of vital organs, which is important since organs can age at different rates. Adjusting lifestyle habits to optimize deficient or excessive metabolites can slow aging.
Dr. Eric Verdin shares his expertise on biological aging clocks that use DNA methylation. He shares that the development of accurate biomarkers of aging is critical for the aging field. However, research on DNA methylation is still ongoing. Dr. Verdin finds that different epigenetic aging algorithms produce inconsistent age estimates—he has scored from age 42 to his actual age of 66 years through various clocks. Dr. Verdin recommends tracking and improving biological age with a single clock type.
2023 emerging trends recapped
- Women’s health is critical to understand and address
- Managing weight is tougher as you age—but there are ways to improve it
- Insulin resistance is critical for metabolic health
- Maintaining cognition is important for healthspan
- Regular exercise elongates healthspan
- DNA impacts healthspan—but DNA isn’t destiny
- There are many biological aging clocks on the market, and using a single clock to track improvements can help improve biological age
