Will eating crabs cause children to suffer from precocious puberty?

Do you like eating crabs? It is the season of crab harvest again. Hairy crabs are flooding people's tongues like a tide. While diners are enjoying their food, some netizens are worried that eating crabs will lead to early puberty in children. Is this true? In fact, before discussing this issue, we need to clarify the following three questions, and then talk about whether it will lead to early puberty in children.

1. Do crabs have sex hormones?

2. Are humans sensitive to sex hormones?

3. Can sex hormones act across species?

These three problems are like a chain of problems. Only when all three problems are true will there be potential impact. Today, I will talk about these three problems and whether they will lead to precocious puberty in children.

01. Do crabs have sex hormones?

The answer is yes.

There happens to be a document titled "Study on Changes in Steroid Hormones and Yolk Protein Content during Ovarian Development of Chinese Mitten Crab" that studies the changes in sex hormones in crabs.

First, the trend of sex hormone changes in hemolymph, from left to right: progesterone, estrone and estradiol

As shown in the figure above, we can see that sex hormones are indeed involved in the development process of crabs, and they also show a trend of dynamic changes.

Also included: Steroid hormone changes in the hepatopancreas

And hormonal changes in the ovaries, a typical gonad:

We can see that during the crab's development period, various steroid hormones are distributed, especially in the ovaries, where the hormone content is the highest.

In fact, sex hormones play a regulatory role in the synthesis of vitellogenin and the maturation of oocytes, and vertebrate-type steroid hormones have been detected in many crustaceans!

So the answer to the first question is: yes.

02. Are humans sensitive to sex hormones?

In fact, the answer to this question is almost affirmative.

A typical example is chemical castration. Have you heard of it? It is a punishment for sex offenders. It uses sex hormones to gradually lose some male characteristics through estrogen and promote the development of some female characteristics, such as breast expansion.

Of course, this is the case when a large dose is used. After all, it is foolish to talk about toxicity without considering the dose. In most cases, low doses of sex hormones will not have a significant effect on people.

However, there is one exception: children.

Children are in a period of rapid development and are more sensitive to hormones. Therefore, hormone interference may have a certain impact on children.

For example, in research on precocious puberty, it was found that children with precocious puberty showed obvious hormonal abnormalities.

It can be seen that sex hormones are one of the important factors leading to precocious puberty.

However, it should be pointed out that it is not certain whether it is exogenous intake, and the cause of precocious puberty is unknown, which may involve multiple factors.

So the answer to the second question is: partially yes.

So we come to the third question

03. Can sex hormones act across species?

The answer to this question is actually yes.

I saw an article before that said sex hormones are different for different species, but this is not true.

Because sex hormones are not proteins, but steroids.

This is an organic molecule in the traditional sense. It is not encoded by genes like proteins, so there will be species differences. So there will be cross-species effects, anyway, it is basically the same.

For example, the same estradiol is the following

It is effective for both humans and other animals.

Okay, that’s all the answers so far.

04. Will crabs cause precocious puberty in children?

In fact, I am very entangled in this conclusion, which is roughly like this:

Children who are in the growth and development stage should avoid excessive and long-term intake of crabs (especially the gonadal part); and should avoid long-term and large intake of foods high in sex hormones.

However, it should be pointed out that:

There is currently no data on whether consuming large amounts of crabs will affect early maturity (research is difficult and unethical), so we can only eat them reasonably.

Finally, we need to remind you that:

1. The sex hormone content of different foods is different and needs to be distinguished.

2. The sex hormone content of the same animal varies at different times.

3. Precocious puberty is an objective problem, and there are many factors that cause it. Currently, at least they include genetic factors, developmental factors, and acquired environmental influences, and it cannot be generalized.

4. Long-term and large-scale intake is the key.

In addition, when consuming seafood, another issue that needs to be paid attention to is: allergies.

Part ref

[1] Che Jie. Study on the changes of steroid hormones and yolk protein content during ovarian development of Chinese mitten crab[D]. Shanghai Ocean University, 2019.

[2] Wang Hexing, Wang Bin, Zhou Ying, Zhao Qi, Wang Na, Fu Zhaowei, Jiang Feng, Jiang Qingwu. Screening and evaluation of antibiotics and sex hormones in Chinese mitten crabs sold in Shanghai[J]. Chinese Journal of Epidemiology, 2015, 36(05): 445-449.

[3] Yan Xuemei, Zhu Hongwei, Ding Zhouzhi. Analysis of characteristics and related risk factors of central precocious puberty in 80 children[J]. Journal of Xinjiang Medical University, 2021, 44(10): 1176-1181.