Home / G. Health and nutrition / Part IND
"Plants have antinutrients."
antinutrients exist, but in the usual amounts and with the usual preparation they matter little, and many of them bring benefits. Cooking, soaking, sprouting and fermenting reduce lectins, phytates and oxalates. Raw beans are harmful; cooked beans are a very nutritious food. And in large studies, eating legumes and whole grains is linked to lower mortality.
Short answer
Antinutrients exist, but cooking, soaking, sprouting and fermenting reduce most of them. Raw beans are harmful; cooked beans are healthy, which is why no one eats raw beans. Many of these compounds, such as phytates and polyphenols, are even linked to benefits. And diets rich in legumes and whole grains are among those most linked to a long life.
For children
Some plants have substances that can cause a bit of trouble, like raw beans. That's why we cook beans! Once cooked, they're tasty and very healthy. And scientists show that cooked beans are good for you.
"Do you eat your beans raw or cooked?"
Como pode aparecer
"Beans have lectins."
"Spinach has oxalates."
"Plants have poisons to defend themselves."
"Vegetables are toxic; meat is the perfect food."
"Antinutrients reduce the bioavailability of minerals."
"Plants feel too." (which is A14)
The strongest version
"Beans have lectins. Spinach has oxalates. Plants have poisons to defend themselves."
Strongest version (steelman):
- P1Plants produce compounds that can reduce nutrient absorption or cause unwanted effects, such as lectins, phytates and oxalates.
- P2Plant-based diets contain more of these compounds.
- P3These compounds can harm health.
- CSo plant-based diets are harmful, and animal foods are safer.
P1 is true. So is P2. The problem lies in P3: with the usual preparation, these compounds have small effects, and several of them are linked to benefits.
The argument is valid. Its soundness fails at P3, which ignores dose and preparation.
Full answer
- a
Reconstruction and diagnosis
The argument ignores dose, preparation and positive effects:
Compound Where it's found What reduces it Real effect Lectins Raw beans and grains Cooking Practically eliminated by cooking Phytates Grains, legumes, seeds Soaking, sprouting, fermenting Slightly reduce mineral absorption; linked to antioxidant effects Oxalates Spinach, beetroot Cooking, variety Relevant only for people prone to kidney stones - b
Where the argument breaks
1. Dose and preparation matter.
Lectins are practically eliminated by proper cooking. Phytates and oxalates are reduced by simple techniques.
2. Many antinutrients bring benefits.
The Harvard School of Public Health's nutrition page summarizes studies indicating that phytates, polyphenols and other compounds may have protective effects, and that the foods containing them are linked to lower disease risk.
3. Foods with antinutrients are healthy.
Legumes, whole grains and vegetables are among the foods most linked to good health and longevity in large studies.
4. Animal foods also contain problematic compounds.
Processed meat is carcinogenic, and red meat, probably carcinogenic (G13).
5. Plants aren't "poison".
That a plant produces defensive compounds doesn't mean it's toxic to those who prepare and eat it in normal amounts.
- c
Data and sources
Source What it says Note Harvard T. H. Chan School of Public Health, antinutrients Antinutrients are reduced by preparation and many have beneficial effects; the foods that contain them are healthy A reference page on nutrition Seidelmann et al., 2018, *Lancet Public Health* Replacing carbohydrates with plant sources was linked to lower mortality Also used in G12 - d
The strongest counter-reply: some people are sensitive
The most serious version grants that, for most people, antinutrients aren't a problem, but points out that some people have sensitivities, such as intolerances or a tendency to kidney stones.
- e
Why the counter-reply doesn't reach the conclusion
Sensitivities call for adjustments, not meat.
People prone to stones can cut back on high-oxalate foods.
These are specific cases.
They don't justify conclusions for everyone.
Variety solves it.
A varied plant diet doesn't depend on any one food.
- f
Back to the moral question
If antinutrients are controlled by preparation and the foods that contain them are healthy, the argument doesn't justify eating animals. The question returns: what justifies their suffering when there are safe, nutritious plant foods?
Reasoning errors
Logical
Is the form valid?
Ignoring the dose
Epistemological
Does the evidence support it?
Not knowing food preparation
Cherry picking
Biases
Confirmation bias
Seeks information that makes plants look suspect
General literature on confirmation bias
Extrapolations
The principle being tested is: "if a food contains a potentially harmful compound, it should be avoided".
If it applied to…Processed meatTap to see
It should be avoided, because it's carcinogenic
Those who use the argument don't conclude this
If it applied to…CoffeeTap to see
It should be avoided, because it has defense compounds
No one concludes this
If it applied to…PotatoesTap to see
They should be avoided, because they contain solanine
No one concludes this
Contradictions
And feels no effect from the lectins.
Which also contain plant defense compounds.
Grain and soy in their feed.
What the argument gets right
What is true
It's true that plants produce defense compounds and that some of them can reduce mineral absorption or cause discomfort. Proper preparation matters, and people with specific conditions should take care.
But
But dose and preparation turn what would be a problem into a detail. Foods rich in antinutrients are among the healthiest there are.
Connections
Usually comes before
Usually comes after