People who ingest more plant foods live longer and suffer fewer illnesses

As We See It: Exponential Knowledge Growth

An explosion of studies over four decades shows that people who ingest more plant foods live longer and suffer fewer illnesses.

By William Faloon.

William Faloon
William Faloon

People who ingest more plant foods live longer and suffer fewer illnesses.1-8

Despite near unanimous agreement today, this concept was not always accepted.

Those who promoted healthy eating faced media persecution and government prosecution. This was done at the behest of corporations that did not want sales of their processed, sugary, and fat-laden toxic foods to be impeded.9

Evidence about healthier diets has been widely disseminated. Yet most Americans do not ingest enough vegetables and fruits.10,11

This has led scientists to study what components of plants are responsible for their protective effects.

A plant compound that has been extensively studied is quercetin. The chart on this page shows that 32 studies about quercetin were published by year 1980.

Move forward to 2022 and a staggering 2,692 new studies were  published that mention quercetin. And in recent years, more reports emanate from randomized controlled trials, which are considered the gold standard of scientific research.

Year 1980 is when we first published. I've had the privilege of interacting (over the past 43 years) with pioneers who educated us about the benefits of incorporating more plant foods in our diet.

We are fortunate to live in this era of exponential knowledge growth!

It is refreshing to see biologic discoveries rapidly transform into practical approaches to combat age-related challenges.

Flavonoids are compounds present in fruits and vegetables.

When consumed as part of a human diet, flavonoids are thought to help protect against various age-associated disorders.13-15

Quercetin is a widely occurring flavonoid found in different plants.

An analysis published in April 2022 looked at previous research and described quercetin's multiple properties. This included quercetin's potential ability to help shield against neurodegeneration.11

The authors of this analysis state that the evidence shows that "quercetin plays a crucial role in the prevention of age-related disorders."16

Quercetin does this, they say, by protecting against inflammation, oxidation, insulin resistance, and other degenerative processes.

They conclude by suggesting that more bioavailable forms of quercetin might yield greater benefits.

Frailty syndrome

Frailty can be defined as "age-related deficits in normal function that involve several body systems."

This definition manifests outwardly as loss of muscle mass, reduced stamina-endurance, declines in strength-cognition, and worsening general fitness.

Frailty predicts greater risk of hospitalization, falls, fractures, dementia, disability, and degenerative illnesses.17-23 It increases vulnerability because of systemic declines in reserve/function. This includes compromised abilities to cope with every day or acute stressors.

The medical community is increasingly recognizing the importance of preventing and treating "frailty syndrome."24

Quercetin and Frailty Onset

In April 2023, the American Journal of Clinical Nutrition published findings from a study that associated higher dietary intake of quercetin with lower odds of frailty.25

The study participants had a mean age of 58.4 years with no frailty at baseline. Dietary intake of different plant flavonoids was carefully evaluated over a 12-year period.

Total dietary flavonoid ingestion did not affect frailty, but every 10 mg/day of higher quercetin intake was associated with 35% lower odds of frailty onset.20

Higher flavonol intake in this study was associated with 20% lower odds of frailty for each 10 mg/day.20

Quercetin is a flavonol. The other flavonoid subclasses showed no association in this correlation-based analysis.

Mechanisms that may explain these declines in frailty onset include quercetin's ability to reduce specific inflammatory factors (like interleukin-6) that cause or contribute to degenerative processes.21

This was an "association" study and not one of the randomized controlled trials that evaluate the effects of quercetin compared to placebo.


One of quercetin's initial effects was noted in allergy sufferers.

An allergy occurs when the body views a substance as harmful and overreacts to it with inappropriate immune/inflammatory responses.

A study published in December 2022 looked at adults with symptomatic allergic reactions induced by pollen. This randomized, double blind, placebo-controlled trial used a bioavailable quercetin daily formula.

After four weeks, several of the allergy symptoms evaluated (eye itching, sneezing, nasal discharge, and sleep disorder) were significantly improved in those taking the quercetin supplement compared with the placebo group.27

The authors concluded, "the results indicated that oral intake of quercetin-containing supplements might effectively reduce some allergy symptoms derived from pollinosis."27


Previous research indicates quercetin helps to neutralize pro-inflammatory factors seen in autoimmune disorders.28,29

In various animal models of autoimmune diseases, like inflammatory bowel disease, multiple sclerosis, lupus, and others, quercetin exerted favorable effects.29-32

In one randomized controlled trial on rheumatoid arthritis, quercetin showed significant improvements in clinical symptoms.28

Quercetin-Enriched Herbs and Memory

Age-associated memory loss is an epidemic problem. Studies that describe the potential of quercetin to cross the blood-brain barrier are fascinating researchers worldwide.33,34

A randomized, double-blind, placebo-controlled trial was published in September 2022. Participants received either placebo or a quercetin-enriched herbal supplement daily over an eight-week period.35

The study subjects who consumed the quercetin-enriched supplement at the higher dose showed improvements across a wide range of sensory, motor, cognitive, and behavioral functions.35

Improvements in working memory may have been associated with suppression of an enzyme (acetylcholinesterase) that degrades acetylcholine and enzymes (such as MAO-B) that degrade dopamine.

These kinds of human results are consistent with findings derived from both observational studies and randomized controlled trials.36-39

More Healthy Life Years!

Recent discoveries demonstrate a remarkable degree of control we can exert over the quality and quantity of our life years.

Clearly, people can live longer, with lower risk of many age-related diseases, by incorporating more plant foods in their diet.

As scientists uncover the biological effects of specific components of plants, aging people can more confidently select nutrients that may improve their healthy lifespans.

There is more published data than ever to validate the effects of plant compounds…and more bioavailable forms from which consumers can select.

For longer life,

For Longer Life

William Faloon


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