2020年12月读毕。
Kindle 书摘：
Most plants, including the vegetables beloved by all the diet experts, contain anti-nutrients that are difficult to digest and even toxic.
Carnivore seems extreme at first glance, but researchers confirm that human evolution was driven by a nutrient-dense diet where calories came predominantly from nose-to-tail animals and secondarily from the plant kingdom.
Our ancestors’ increasing consumption of nutrient-rich animal foods was strongly correlated with an increase in brain size. This was the primary catalyst for us to branch away from our leaf-chewing ape cousins and ascend to the top of the food chain.
Eating animals nose to tail is what made us human! Transitioning from scavengers to hunters appears to have been the defining moment in our evolution as humans.
The upper limit for protein in our diets seems to be about 40 percent of our total calorie intake, beyond which point we might exceed the liver’s ability to process this macronutrient. This means that 60 percent of our caloric needs must be met by either fat or carbohydrates.
Another significant difference between humans and our distant primate relatives is the design of our shoulder joint. It’s truly a masterpiece of evolution.
What if I were to tell you that at one point in our evolutionary history, our health went from appearing pretty good to being basically abysmal almost overnight? Well, this is exactly what happened about 12,000 years ago during the Neolithic Revolution when we began farming and joined “the cult of the seed.”
They have the same agenda as the rest of the living things on this planet: to proliferate and pass their DNA on to future generations.
There are literally hundreds of thousands of chemicals produced in the plant kingdom that can harm us.
The largest category is the phytoalexins—chemicals directly produced by plants to ward off attack from insects, fungi, and animals.
Lectins are another category of toxic substances in plants that you need to know about and avoid
Oxalates are another chemical spike found in plants.
The earth is thought to be about 4.5 billion years old, and the first evidence of life dates back to around 3.5 billion years ago.
In fact, multiple studies have shown that supplementation with plant “antioxidant” molecules do nothing to improve antioxidant status in humans and are often associated with worse outcomes.
While humans have been feasting primarily on animal foods for the last 2 million years, similar selective pressures from plant toxins have not been present for us, and we appear to be much less adapted to eating significant amounts of plants for long periods of time.
Perhaps you’ve heard of the compound sulforaphane associated with all sorts of fancy health claims from “cancer fighter” to “antioxidant hero.” This molecule is an isothiocyanate derived from the glucosinolate molecule, glucoraphanin. In this case, sulforaphane is formed when myrosinase does its enzymatic work on glucoraphanin, and out of this process come magical rainbow unicorns. While that’s the popular narrative that supplement manufacturers and many in the health space want you to believe, I’m not buying it and you shouldn’t either.
Sulforaphane is so toxic that it can’t be present in a healthy broccoli plant, or it would cause massive damage due to it’s strong capacity as a pro-oxidant.
Cases of hypothyroidism induced by over-consumption of crucifers have been reported even in westernized populations but are extremely common in underdeveloped regions of the world.
Sulforaphane has been shown to have potential benefit in cancer-fighting models because it damages cells and can induce programmed cell death, or apoptosis. But when introduced into our bodies, it’s going to target our healthy cells too.
When we eat cruciferous vegetables, glucosinolates like glucoraphanin combine with myrosinase during the chewing process, forming isothiocyanates like sulforaphane.
A small fraction of this sulforaphane is absorbed and rapidly detoxified in the liver through a process of conjugation to glutathione. It is then excreted in the urine.
Plant compounds like glucosinolates and polyphenols do not participate directly in our biochemistry. Instead, they often trigger defensive reactions in our body.
While it is true that sulforaphane does act as a pro-oxidant, by activating the NRF2 system it induces the formation of our own endogenous antioxidants, like glutathione.
None of the other plant molecules like polyphenols act directly as antioxidants either—they also act as pro-oxidants and turn on the NRF2 system.
While we are bombarded with mainstream messaging in the health space that tells us fruits and vegetables are good for us and that we benefit from “antioxidants” and “phytochemicals,” scientific literature repeatedly states otherwise.
We’ve been told that plant molecules are intrinsically benevolent, can’t harm us, and exist to improve our health—and we’ve blindly accepted these notions.
When faced with the need to consume cruciferous vegetables, like cabbage, our ancestors discovered that they could detoxify many of the harmful compounds through fermentation.
It should also be noted that cooking Brassica vegetables degrades myrosinase, but sulforaphane can still be formed by myrosinase from gut bacteria, so even with cooked broccoli, you’ll be getting a dose of this isothiocyanate.
In the plant kingdom, polyphenols serve unique roles as phytoalexins and as plant pigments.
The vast majority of the data suggesting benefits from polyphenols is derived from epidemiological research. But epidemiology doesn’t actually involve any sort of intervention.
Unfortunately, interventional studies in the world of nutrition are seldom done.
I strongly believe that most, if not all, chronic disease we suffer from today is inflammatory and autoimmune in nature.
When food causes inflammation, the main pathway by which it does so is by damaging the gut with the subsequent activation of our immune system army that resides on the other side of the delicate intestinal epithelial cell layer.
In the animal foods that compose our diets, there are no chemical toxins intrinsically present—end of story.
Invariably, plant molecules do not act directly as antioxidants in the human body, nor would this sort of disruption of our redox balance be advantageous.
One of the biggest problems with the flavonoids is their ability to act as endocrine disruptors.
not only are the nutrients in plant foods less bioavailable, but the presence of these digestive enzyme inhibitors, like tannins and other polyphenols, further contributes to the lower nutritive value of plant foods.
As we touched on previously, molecular pro-oxidants, at even small doses, possess damaging side effects like endocrine disruption, and inhibition of detoxification systems, whereas the environmental inputs do not. This is the key difference between hormetic plant compounds and environmental hormetics.
In humans, oxalic acid is produced as a waste product and excreted in the urine.
Oxalates clearly get deposited into many tissues in our bodies in a pathological way, but the major burden of suffering related to them comes from calcium oxalate kidney stones.
Over 75 percent of kidney stones are made from calcium oxalate.
Many studies have also shown that green tea and black tea contain significant amounts of oxalates, and tea is further problematic due to its high-tannin content, which acts as a digestive enzyme inhibitor and could potentially cause damage to the lining of our gut.
The concept of lectins can be a bit confusing, but simply put, they are a special type of protein that binds to glycoproteins on the surface of or within our cells.
