Nearly 25 years of studying longevity has taught me these are the key factors for a long, happy life.

Dr. Andrea Maier is a geroscience expert with over 20 years of experience in the field, having studied the mechanisms of aging and their implications for health and longevity. In the last decade, she has applied her knowledge in clinical practice.

She, an internal medicine specialist in Singapore, tests patients' biomarkers of aging, including organ health.

Maier proposes practical solutions to enhance a patient's chances of living longer, such as modifying their diet based on their microbiome, engaging in specific physical activities, adjusting their sleep habits, or taking supplements based on their current body requirements.

Not only does Maier give advice and study, she also follows some of it herself.

CNBC Make It interviewed Maier about her personal habits for longevity and what she does to stay happy and healthy.

This interview has been edited and condensed for clarity.

What a longevity expert does for a long, happy life

What are some specific actions you take to enhance your brain's sharpness and improve your focus?

Maier believes that brain health is often overlooked. It's crucial to assess your cognitive abilities. Everyone should undergo brain tests to determine their short-term and long-term memory capabilities, as well as their brain's ability to multitask.

In Singapore, there is a gym called SPARKD that offers an innovative approach to fitness by combining physical training with brain fitness exercises. On a treadmill, you can train your muscles, bones, and cardiovascular fitness while also being exposed to memory tasks. This combination is both exciting and effective in improving overall fitness.

How proficient are you in doing math while on a treadmill? How much do you slow down?

I believe that using the brain is crucial, and I am always doing it.

How would you rate your social fitness?

I recently returned from Paris and Berlin, where I enjoyed some quality time. Now, it's time to work for a few days or weeks before I have more quality time with others.

Social interactions and a sense of purpose are crucial for maintaining routine and preventing detrimental habits in individuals who lack social interactions and a job that provides purpose.

Before engaging in social interactions, assess your current emotional state. Are you feeling isolated, depressed, or worried? I do the same. However, it's not just about the duration, but also the quality and significance of the interactions.

We are social creatures, and it's essential for our brain health to engage in social interactions rather than focusing solely on ourselves.

How important is it for you to consider longevity when planning your daily diet?

I never received a lesson on diet as a physician, which is unfortunate, but that was the curriculum at the time. Therefore, physicians of my age were not taught what to do regarding diet.

Since I was three, I've been a vegetarian for ethical reasons, and it appears to be beneficial to my health as well.

I'm 46 and still consuming Diet Coke.

I often skip breakfast, which I didn't realize was linked to intermittent fasting or time-restricted eating 20 or 30 years ago.

I usually eat my first meal at two o'clock in the afternoon, but sometimes it's in the evening. These eating habits were already part of my lifestyle before I learned about their potential benefits.

Not everyone needs to be vegetarian or vegan and practice intermittent fasting.

It is crucial to have good quality intake, and observing the results of your eating habits is equally important.

What are the experts in your field currently reading?

I devote at least one hour each day to either reading or listening to news, including the BBC news podcast and various newspapers, such as the New York Times.

It is crucial to adhere to and gain knowledge from a variety of news sources, as it is essential to comprehend the connection between health and longevity in a broader context. We frequently overlook this context when we only rely on one source.

We acknowledge that increasing life and health expectancy is necessary, but we must also consider the political and environmental factors that impact our ability to implement these goals, and prioritize what is essential for specific societies at this time.

A longevity expert's 4 daily habits

Dr. Maier's longevity practices include methods to maintain her health and boost her happiness.

• For brain health: Using her brain often and being open to change
• She alternates between prioritizing work and quality time, depending on her current needs for social fitness.
• She adheres to a vegetarian diet, excluding red meat, white meat, and fish.
• For her media diet: Staying up-to-date with the latest news

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