Chapter 165
Power Plants
There are thousands of phytonutrients that will never make it onto the ingredient list of a box of muesli, but still play a role in reducing the risk of chronic disease—and those are only the ones we know about. The terms phytonutrient and phytochemical refer to natural plant compounds that can affect our health. (Phyto- comes from the Greek phyton, “plant.”) They are not considered “essential” nutrients like vitamins, because we can survive without them. Instead, they are viewed as “longevity-essential,” meaning we need them in order to live as long as possible. In that respect, they are like dietary fiber—important for optimal health and longevity, but not indispensable, as coma patients can live for years on an intravenously administered mixture of sugar water, electrolytes, amino acids, vitamins, and some essential fats and trace elements.
How many people die nowadays from vitamin deficiency, for example from scurvy, compared with the number who die from a lack of plant nutrients? Worldwide, an estimated 7.8 million premature deaths per year are attributed to inadequate fruit and vegetable intake—that is, fewer than eight servings per day. Millions of lives are at stake, and the scale in the produce section tips the balance.
If you add up, in the United States alone, all the fatal cancers, strokes, heart attacks, and other deaths that could have been prevented with more fruits and vegetables, you end up at about 450 000 per year. There is a phytonutrient-deficiency pandemic that could be halted with a few extra servings of plant nutrients per day. Yet the pandemic is not getting better, but worse. In recent decades, diet quality has continued to decline. Consumption of fruits and vegetables (with the exception of potatoes) has fallen by more than half, and consumption of legumes, another important source of phytonutrients, by about 40 percent. At the same time, more and more saturated fat is being eaten. Only about 1 in 250 people even reaches 80 percent of the dietary recommendations of the American Heart Association.
Maybe people simply don’t grasp the power of plants. Just think of the first phytochemical isolated from poppy in 1804: morphine. In the 4th century, China had the first manual of emergency medicine, in which wormwood was recommended against malaria. 1700 years later, this was immortalized with the Nobel Prize in Medicine for the discovery of the phytochemical artemisinin, which to this day is used as a component of the most effective combination therapies against the scourge of humanity, malaria. In my video see.nf/herbs2drugs I discuss more impressive examples.
Polyamory
In developing dietary concepts to combat age-related diseases, polyphenols are right out in front. More than 8000 different polyphenols have been identified, but only a small portion has been cataloged. Still, such a wealth of data supports their protective function strongly enough that minimum daily polyphenol amounts have been proposed. In see.nf/polyphenols I provide an overview of what they do and why, and I mention the one flavonoid source that is associated with increased mortality: grapefruit, in part because grapefruit suppresses a number of detoxification enzymes in the gut.
Natural Geroprotectors
Geroprotectors are substances that increase longevity and/or have other anti-aging properties. To date, more than 200 have been found (see geroprotectors.org). Some of the most potent—some that work even better than synthetic preparations—are natural plant extracts from simple herbs and spices such as celery seed. There are phytonutrients that can increase maximum life span in animals by as much as 78 percent.
Plant extracts that have been shown to extend the life span of lower organisms include açaí, apples (including the boring Red Delicious), asparagus, blueberries, cinnamon, cocoa, corn, fenugreek seeds, grape skins, holy basil, peach, pomegranate, rose, and turmeric. A few increase the life span of mammals such as mice, and these—for example, lemon—are tested on inbred strains that age very rapidly.
Many of the “superfoods” that extend the lives of weakened mice have no significant effects on robust, long-lived mice, and if they do, then perhaps because of an unconscious restriction of food intake. For example, mice fed a turmeric preparation lived longer than the control mice, but weighed about 3 percent less, suggesting they ate less. (Maybe they didn’t like curry.) Dietary restriction alone could be responsible for the greater life span. When the researchers subsequently fed the mice isocalorically rather than ad libitum, so that all the mice ate the same amount, the benefit of turmeric appeared to disappear.
Speaking of life extension through dietary restriction: Could the hormetic or xenohormetic benefit of phytonutrients undermine the greater life span from the stress of restricted caloric intake? A mixture of synthetic antioxidants completely nullified the life-extending effect of a 20 percent restricted diet, but when intermittently fasting mice were given polyphenols from blueberries, pomegranates, and green tea, they lived even longer than if they had only fasted intermittently. The life-extending effect was further enhanced by the phytonutrients. The researchers suspect that in mice, fasting every other day does have a net positive effect on life span, but also brings harmful stress that can be successfully countered by polyphenols.
Plants, Not Pills
If phytonutrients are so healthy, why not just take supplements with plant extracts, instead of going to the trouble of eating the plants themselves? Because—aside from problems like mislabeling, contamination, and adulteration, which are common in the poorly regulated dietary supplement market and which we have already discussed—the issue of dosing also arises. Taking polyphenol supplements can lead to a higher blood concentration than if you eat the polyphenols. With hormesis, less can be more.
A number of examples of how isolated phytochemicals and plant extracts at certain dosages extend life but at higher doses shorten it can be found in see.nf/dosing. After all, many flavonoids are “nature’s pesticides” and protect plants from predators like us. We evolved alongside plants and can block these defenses, and thanks to hormesis, a tiny dose of poison can actually benefit us, but too much of the toxin is toxic. To paraphrase a review on the anti-aging effects of polyphenols: supplements are more likely to be overdosed than salad.
Synergy in Plants
Some phytonutrients are so potent that effective doses can be put into capsules and compared in controlled studies with a whole-food diet. The sesame phytonutrient sesamin, for example, extends the life of C. elegans and fruit flies. To find out whether it also has clinical effects, researchers compared a daily dose of 2.5 grams of ground black sesame seed in capsules with a placebo. Within a month, a dose of less than a teaspoon of sesame seeds per day lowered systolic blood pressure by eight points in middle-aged men and women. If that effect persisted, it would reduce stroke risk by more than 25 percent.
The disadvantage of studies with whole foods is that you can never be entirely sure which component—or which components—are working. Was it sesamin or other sesame phytonutrients such as sesamol, sesamolin, or the anthrasesamones A, B, C, D, E, or F? In a sense, no one knows for sure, but who cares as long as it works? Natural products, perishable and relatively unprofitable, are hard to patent, so Big Pharma and supplement manufacturers (often one and the same company) try, with a reductionist approach, to find the “magic bullet,” the active ingredient in foods. But in doing so, they overlook synergy. Sometimes the whole food is more than the sum of its parts.