We have discussed in our previous column the discovery at the start of this century of a hormone manufactured mostly by the liver, going by the acronym FGF21 which is now called the ‘longevity hormone’. 

Indeed, in experiments with mice, it was observed that when the animals were injected with FGF21 it increased their lifespan by 30 to 40 percent and without the need to decrease their food intake. Efforts by the pharmaceutical industry so far to manufacture chemical substitutes of this hormone have been hampered by unwanted side effects. 

So the question we should ask is whether there are natural ways whereby the production of FGF21 by the liver could be increased. Studies in mice show that FGF21 is increased just after 6 hours of fasting, so it would indicate that if humans would adopt a fasting regime, which is popular for weight loss, it would increase FGF21 production with its beneficial effects.

Unfortunately, in humans, one needs to fast at least for one week before a notable surge in FGF21 occurs. So this is an unsustainable proposition. But there are more practical solutions to get the benefit from increasing FGF21 production: exercise and diet. Exercise boosts FGF21 levels, which may in fact be one of the underlying causes why exercise is so good for us. 

When researchers compared various types of exercises, they found that resistance training was the most effective: following two groups of volunteers doing daily exercises for eight weeks, they found that resistance exercise caused a 42 percent increase in FGF21 versus a 25 percent increase in the aerobic exercise group. 

The moral of the story is that you should combine the exercises: brisk walking as well as weight training! I can share a personal experience: many of us have sedentary jobs and work from computer stations. One trick is to work for 50 minutes and then take a 10-minute break to do your exercises. All it takes is three 10 minutes a day to do your exercises. If you cannot do it at work, do it at home before or after work! But even if somehow you cannot find the time to exercise, there is another sure way to boost your liver’s FGF21 production: simply follow the whole food plant-based (WFPB) diet that METI recommends for staying healthy or regaining your health. 

Increased FGF21 production seems to be linked to the high amount of fiber you find in starchy foods: that means root crops (like taro, yams, and sweet potatoes), but also breadfruit and green bananas, whole grains, and beans. 

In a previous column, we discussed that fiber in the diet is what good gut bacteria like to eat that makes them produce short-chain fatty acids (SCFA): like butyrate. Recent research provides evidence that butyrate increases the production of FGF2, which offers further proof of the wide-ranging beneficial effects of SCFA.  

The other hallmark of the WFPB diet is that it offers less protein than found in the Western animal-based diet. Again, recent medical research has confirmed that circulating FGF21 levels are increased dramatically when you eat a lower protein diet: over 150% increase within four weeks! This FGF21 connection would then explain why people following the WFPB diet –like those in the ‘Blue Zones’ (areas in the world that are famous for having the highest proportion of centenarians among their populations – such in regions in Greece, Sardinia, and Costa Rica as well as the populations of Okinawa and Loma Linda, California) - live longer than those eating an ‘omnivore’ or animal-based diet. The research found that FGF21 levels were markedly higher in vegans compared with omnivores. Further, when omnivores were switched to vegetarian diets: just only after four days FGF21 levels increased by 232 percent, just by eliminating meat from the diet.

In conclusion, FGF21 seems to be the systemic enhancer of longevity. It can be boosted by following the WFPB diet. What are you waiting for to start to change your diet to get optimal health and a ‘scientific’ guarantee that you will live longer? We invite you to visit METI’s Healthy Living Clinic at House No. 51 at Motootua (across from the Kokobanana Restaurant) to become acquainted with the METI whole food plant-based diet and Lifestyle Change programs. Or call us at 30550. Learning how to follow these Programs might be your ‘game changer’!