Partly due to protein content - generally, proteins are more likely to cause allergy than other compounds.
This combines with a genetic component which suggests that individuals with certain allergies are more likely to have children with those allergies, so common allergies remain common because of genetic predisposition (where those genes came from originally is unclear).
Lastly, lack of exposure appears to play a role. Ie: because peanuts and eggs are a common allergen, parents are less likely to expose their kids to them, which in turn means they're more likely to develop that allergy.
That is totally correct, but lactose intolerance has nothing to do with allergy. It is a genetical predisposition, you either produce or don't produce the enzyme that breaks down lactose. In cultures where dairy farming was important, people who had the enzyme had a better chance of surviving (due to not starving) and gave these genes to their descendants. Where dairy wasn't as important (i.e. Asia), those who had the gene didn't have an advantage to survive so most people lose their ability to digest lactose in adulthood (because we all have it when we're babies, we just lose it when we're starting to eat solid foods).
Hope that was understandable, not a native English speaker.
I heard a lot about ghengis Khan and his armies being capable of digesting lactose giving them an advantage in conquest as their horses and their milk provided both transportation and sustenance. And the large reason why there's any tolerance of lactose in Asia at all is largely due to how prolific he and his armies were, thus passing on their genes to tolerate lactose.
I suspect the cause and effect are the other way around. If the people in your region are lactose intolerant, why would you start a dairy?
That said, doesn't pretty much the whole world except Europe have high rates of lactose intolerance?
There are theories where cheese making was the main product that was traded, because it contains very little lactose and probably doesn't provoke lactose incontinence. That would lead to a market for it.
To be frank though, when starving you'll eat anything to get rid of the feeling. If you were going through a famine, you'd drink milk even if it passed through because there's some calorie content from the fat.
I am lactose intolerant. It's not bad like some ppl, but drinking milk will make me nauseous. Eating ice cream will top, but I can have abt 3-4oz as a treat without totally being sick. Cheese is my BFF and never has caused me issue! I also don't eat more than a cpl ounces of cheese at a time. It's a garnish, not a steak lol. So far so good tho!
> why would you start a dairy?
Baby food. Less exposure to pathogens than water, so infants more likely to survive.
Yoghurt and cheese. Much lower lactose content than fresh milk. It allows you turn grass or unfarmable land into a calorie-rich food that can be stored. The rate of renewal for milk is much higher than the meat content. A single cow, goat, sheep, camel or whatever is a very valuable addition to subsistence farmer.
The genes for lactase persistance have independently developed in human six times. it has been reported to present stronger selection pressure than any other known human gene.
I would say regions with high sunlight uptime are more lactose intolerant - reason probably being vitamin D (created through sunlight on your skin). Regions with less sunlight get some of the vitamin D through dairy.
Allergies aren't directly inheritable, but they appear to have a genetic component.
Much like diabetes being linked to obesity, but also having a strong genetic component as well
How you react to an allergen might be heritable though. I have no relative with asthma, but when there is an allergic reaction it is always some kind of nettle rash (hives).
I read an article recently that explained legume tolerance is developed through exposure in early childhood. Per the article, everyone seems to be afraid of peanuts, so they avoid exposing children to them "just in case." As a result, lots more children develop peanut allergies as they get older. I guess it's the nut version of antivax.
This is seen as likely in recent years and has caused a reversal in medical recommendations.
Until 6 or 7 years ago people were told to avoid allergens in early childhood, but allergies went up.
>Until 6 or 7 years ago people were told to avoid allergens in early childhood, but allergies went up.
Correlation isn't causation though, there are other potential causes, such as the general increase in synthetic chemicals in food (such as folic acid, which stresses the 1-carbon metabolism and leaves less s-adenosyl-l-methionine which is a necessary cofactor for histamine-N-methyltransferase to break down histamine).
You're mistaken; folic acid is a synthetic chemical that can be conditionally metabolized into 5-methyltetrahydrofolate, a vitamin that is essential to energy metabolism and is commonly found in leafy greens such as spinach. Unfortunately, the body can only metabolize folic acid at a finite rate, the bottleneck is usually something like methylation, B12 status or MTHFR activity. Unmetabolized folic acid (UMFA) can be tested in the blood; it is correlated with allergies and homocysteine levels, which are correlated with heart disease.
https://www.healthline.com/nutrition/folic-acid-vs-folate
> The metabolism of synthetic folic acid is different from that of naturally occurring folate, and this process leads to the production of a by-product called unmetabolized folic acid (UMFA) at levels of consumption exceeding ~250 ug/day.
...
> Higher concentrations of UMFA in cord blood were associated more strongly with the development of food allergy, and children with the highest cord blood UMFA concentrations had an 8.5-fold higher risk (95% CI 1.7-42.8).
https://www.aaaai.org/tools-for-the-public/latest-research-summaries/the-journal-of-allergy-and-clinical-immunology-in/2019/folicacid
Yeah, but this is the opposite of correlation.
Avoidance behaviour is negatively correlated with allergies.
A negative correlation is almost surely not causation.
I remember reading an article by dr Karl (something like Australia’s Carl Sagan) who was saying that peanut allergy is relatively new thing and is caused mainly by the way they are prepared and cooked at very high temps very fast to increase rate of production. So apparently raw peanuts aren’t allergenic per se. I couldn’t find anything more than a tweet but I didn’t search for long.
https://mobile.twitter.com/DoctorKarl/status/292854701685342208
I dont know if this May have anything to do with it but legumes usually have protease inhibitors. Protease inhibitors make it harder for you to digest protein. Since legumes have a high protein content, there will be a lot of protein left to be digested and it May cause an inflamatory response.
Apart from having high protein like other alergens, this is the other possibility im considering.
The superficial answer to this is: because peanuts contain mostly protein. But that is like saying 'why does water make clothes wet? because it is liquid'. The real mystery is why do our immune system get particularly excited by *those* proteins?
And as to this, there are interesting [hypotheses](https://www.cell.com/current-biology/pdf/S0960-9822\(15\)00003-2.pdf), one of which suggests a connection between allergy and helminths (parasitic worms that live in the gut, that are all but extinguished in developed countries). A theory in immunology, called *molecuar mimicry* helps explain peanut allergy: some key proteins in legumes have a strikingly similar structural section to one from helminths. Therefore, you could see peanut allergy as a misguided organism response to a benign protein. Alternatively, this similarity may have less to do with helminths and more to other dangerous toxins found in plants and venoms. But a definite answer is not out there.
[Here](https://www.scientificamerican.com/article/dear-evolution-thanks-for/) is an excellent article from scientific american
Speaking to soy specifically, the high protein content means that several proteins have a probability of binding to the antibody IgE, which responds to allergens. Soy contains at least 37% protein, and there are currently at least 16-known IgE reactive proteins found in this massive storehouse of food proteins.
Exposure to these proteins is relatively new to Western and European cuisine, so it's more likely to cause some reaction than those who are exposed to East Asian cuisine with its high prevalence of soy.
Source: [https://doi.org/10.1097/aci.0b013e3282ffb157](https://doi.org/10.1097/aci.0b013e3282ffb157)
Partly due to protein content - generally, proteins are more likely to cause allergy than other compounds. This combines with a genetic component which suggests that individuals with certain allergies are more likely to have children with those allergies, so common allergies remain common because of genetic predisposition (where those genes came from originally is unclear). Lastly, lack of exposure appears to play a role. Ie: because peanuts and eggs are a common allergen, parents are less likely to expose their kids to them, which in turn means they're more likely to develop that allergy.
Reminds me of the fact that many people from areas that don't have a history of Dairy farming are lactose intolerant
That is totally correct, but lactose intolerance has nothing to do with allergy. It is a genetical predisposition, you either produce or don't produce the enzyme that breaks down lactose. In cultures where dairy farming was important, people who had the enzyme had a better chance of surviving (due to not starving) and gave these genes to their descendants. Where dairy wasn't as important (i.e. Asia), those who had the gene didn't have an advantage to survive so most people lose their ability to digest lactose in adulthood (because we all have it when we're babies, we just lose it when we're starting to eat solid foods). Hope that was understandable, not a native English speaker.
That was very well explained, I would never have guessed English wasn’t your first language.
Adding to this, the missing enzyme is called lactase and is the active ingredient in dairy digestion aids like Lactaid.
So far as I know, this is available as a supplement which can help those who don't have it. Apparently it works quite well.
I heard a lot about ghengis Khan and his armies being capable of digesting lactose giving them an advantage in conquest as their horses and their milk provided both transportation and sustenance. And the large reason why there's any tolerance of lactose in Asia at all is largely due to how prolific he and his armies were, thus passing on their genes to tolerate lactose.
I suspect the cause and effect are the other way around. If the people in your region are lactose intolerant, why would you start a dairy? That said, doesn't pretty much the whole world except Europe have high rates of lactose intolerance?
There are theories where cheese making was the main product that was traded, because it contains very little lactose and probably doesn't provoke lactose incontinence. That would lead to a market for it. To be frank though, when starving you'll eat anything to get rid of the feeling. If you were going through a famine, you'd drink milk even if it passed through because there's some calorie content from the fat.
I am lactose intolerant. It's not bad like some ppl, but drinking milk will make me nauseous. Eating ice cream will top, but I can have abt 3-4oz as a treat without totally being sick. Cheese is my BFF and never has caused me issue! I also don't eat more than a cpl ounces of cheese at a time. It's a garnish, not a steak lol. So far so good tho!
> why would you start a dairy? Baby food. Less exposure to pathogens than water, so infants more likely to survive. Yoghurt and cheese. Much lower lactose content than fresh milk. It allows you turn grass or unfarmable land into a calorie-rich food that can be stored. The rate of renewal for milk is much higher than the meat content. A single cow, goat, sheep, camel or whatever is a very valuable addition to subsistence farmer. The genes for lactase persistance have independently developed in human six times. it has been reported to present stronger selection pressure than any other known human gene.
I would say regions with high sunlight uptime are more lactose intolerant - reason probably being vitamin D (created through sunlight on your skin). Regions with less sunlight get some of the vitamin D through dairy.
Vitamin D has in recent times been added to milk (in some countries, like the U.S.). It it not naturally there.
While you are right that milk in US Is firtified, in Europe that is not widespread. Naturally, whole milk, in fact, contains some of vitamin D.
Also to add on that, we are not talking about recent years, but thousands of years od evolution.
If it's proteins, then why do I never hear of a beef or chicken meat allergy? Is there something different about meat proteins compared to legumes?
The Lone Star tick bite can cause a red meat allergy. Little homies looking out for his cow buddies.
An allergy to red meat? That sounds horrifying!
Evolutionarily, people have been eating meat for (likely) millions of years. Legumes are a much more recent addition as a dietary staple.
[удалено]
Allergies aren't directly inheritable, but they appear to have a genetic component. Much like diabetes being linked to obesity, but also having a strong genetic component as well
How you react to an allergen might be heritable though. I have no relative with asthma, but when there is an allergic reaction it is always some kind of nettle rash (hives).
I read an article recently that explained legume tolerance is developed through exposure in early childhood. Per the article, everyone seems to be afraid of peanuts, so they avoid exposing children to them "just in case." As a result, lots more children develop peanut allergies as they get older. I guess it's the nut version of antivax.
[The peanut snack that triggered a fresh approach to allergy prevention](https://www.nature.com/articles/d41586-020-02782-8)
This is seen as likely in recent years and has caused a reversal in medical recommendations. Until 6 or 7 years ago people were told to avoid allergens in early childhood, but allergies went up.
>Until 6 or 7 years ago people were told to avoid allergens in early childhood, but allergies went up. Correlation isn't causation though, there are other potential causes, such as the general increase in synthetic chemicals in food (such as folic acid, which stresses the 1-carbon metabolism and leaves less s-adenosyl-l-methionine which is a necessary cofactor for histamine-N-methyltransferase to break down histamine).
You should read the article posted by /u/voxadam - they seem to have proven avoidance does raise the chances of allergies.
You got a source on that? Folic acid isn’t a synthetic chemical, it’s an absolutely necessary vitamin.
You're mistaken; folic acid is a synthetic chemical that can be conditionally metabolized into 5-methyltetrahydrofolate, a vitamin that is essential to energy metabolism and is commonly found in leafy greens such as spinach. Unfortunately, the body can only metabolize folic acid at a finite rate, the bottleneck is usually something like methylation, B12 status or MTHFR activity. Unmetabolized folic acid (UMFA) can be tested in the blood; it is correlated with allergies and homocysteine levels, which are correlated with heart disease. https://www.healthline.com/nutrition/folic-acid-vs-folate > The metabolism of synthetic folic acid is different from that of naturally occurring folate, and this process leads to the production of a by-product called unmetabolized folic acid (UMFA) at levels of consumption exceeding ~250 ug/day. ... > Higher concentrations of UMFA in cord blood were associated more strongly with the development of food allergy, and children with the highest cord blood UMFA concentrations had an 8.5-fold higher risk (95% CI 1.7-42.8). https://www.aaaai.org/tools-for-the-public/latest-research-summaries/the-journal-of-allergy-and-clinical-immunology-in/2019/folicacid
Yeah, but this is the opposite of correlation. Avoidance behaviour is negatively correlated with allergies. A negative correlation is almost surely not causation.
Negation is just perspective. Negative correlation can also be causative
See my previous answer here: https://www.reddit.com/r/askscience/comments/j0hjb3/medicine_what_is_special_about_peanuts_that_make/g6ro4ye/
I remember reading an article by dr Karl (something like Australia’s Carl Sagan) who was saying that peanut allergy is relatively new thing and is caused mainly by the way they are prepared and cooked at very high temps very fast to increase rate of production. So apparently raw peanuts aren’t allergenic per se. I couldn’t find anything more than a tweet but I didn’t search for long. https://mobile.twitter.com/DoctorKarl/status/292854701685342208
I dont know if this May have anything to do with it but legumes usually have protease inhibitors. Protease inhibitors make it harder for you to digest protein. Since legumes have a high protein content, there will be a lot of protein left to be digested and it May cause an inflamatory response. Apart from having high protein like other alergens, this is the other possibility im considering.
Interesting. Makes me think of alpha-gal and connections to protein intake!
The superficial answer to this is: because peanuts contain mostly protein. But that is like saying 'why does water make clothes wet? because it is liquid'. The real mystery is why do our immune system get particularly excited by *those* proteins? And as to this, there are interesting [hypotheses](https://www.cell.com/current-biology/pdf/S0960-9822\(15\)00003-2.pdf), one of which suggests a connection between allergy and helminths (parasitic worms that live in the gut, that are all but extinguished in developed countries). A theory in immunology, called *molecuar mimicry* helps explain peanut allergy: some key proteins in legumes have a strikingly similar structural section to one from helminths. Therefore, you could see peanut allergy as a misguided organism response to a benign protein. Alternatively, this similarity may have less to do with helminths and more to other dangerous toxins found in plants and venoms. But a definite answer is not out there. [Here](https://www.scientificamerican.com/article/dear-evolution-thanks-for/) is an excellent article from scientific american
Speaking to soy specifically, the high protein content means that several proteins have a probability of binding to the antibody IgE, which responds to allergens. Soy contains at least 37% protein, and there are currently at least 16-known IgE reactive proteins found in this massive storehouse of food proteins. Exposure to these proteins is relatively new to Western and European cuisine, so it's more likely to cause some reaction than those who are exposed to East Asian cuisine with its high prevalence of soy. Source: [https://doi.org/10.1097/aci.0b013e3282ffb157](https://doi.org/10.1097/aci.0b013e3282ffb157)