What is carrageenan? Where does it come from? And why do we have to worry about this additive?
Carrageenan is an additive often used as a thickener or stabilizer. More than often, we should say: very often. In fact, it is present as an additive in many products that we usually consume.

From dairy products to industrial cheeses, up to creams, puddings, spoon desserts, industrial ice cream, many preparations for spoon desserts such as freeze-dried puddings, long-life cream, pastes and pates, frozen foods, candies .

Finally, it is found in vegetable milks, in toothpastes, in many drugs, in some beers, in some yogurts, gums, lollipops, etc., up to artificial milks for infant nutrition, chocolate milk, soluble preparations for drinks.

Carrageenan is almost always present in many creamy preparations, in jellies, in confectionery or dairy products. If we do not find carrageenan written, it is very likely to find this additive under the acronym E407 in the list of ingredients. 

But what is carrageenan?
It is a polysaccharide of the mucilage family extracted from three families of red algae originally from Ireland (but which obviously are not found only there), namely  Condrus, Eucheuma  and  Gigartina.

The FDA and also EFSA consider carrageenan a safe additive. However, there is a but. These safety assessments of many additives are often in the process of subsequent updates.

In 2019 EFSA should , in the light of new studies, draw up new warnings and limitations on the subject of food additives. In April 2018, the FDA revised the carrageenan page, noting that its use is safe. 

However, there are scientific studies that instead speak of carrageenan and its side effects in the intestine, which show that this additive would actually be a health hazard. Here they are in summary.

CARRAGENIN SIDE EFFECTS

In 2016 in America the Cornucopia Institute voted, together with the National Organic Standards Board (NOSB), a petition to exclude carrageenan from the food industries.
But, according to what they say, they would have been snubbed by the Trump presidency.
The Cornucopia Institute has long published a dossier on carrageenan, which can be consulted (in English) at this address. 

In this document we read numerous studies both in vitro and in vivo, and observations on side effects complained by consumers of products containing carrageenan, and reported by doctors.

These include colon problems, excessive intestinal fermentation, irritable colon, spasms, ulcerative colitis.
Doctors reported symptom regression in all patients who excluded carrageenan-containing products from their diet.
According to what we read, the chemical structure of carrageenan causes an immune response in the body, and related inflammation.

And this would be known as early as 1960, when the first results from tests on the safety of carrageenan as a food additive appeared. Researchers reported abdominal swelling, spasms, ulcers and other inflammatory states in rats, and even cases of colon cancer. A new study appeared in 1978 , another in 9181.

In 2001 a meta-analysis edited by Dr. Joanne Tobacman came out , in which we read that, in the light of the studies collected, the use of carrageenan as a food additive should be re-evaluated.

The same doctor talks about it again in 2018 , in a study in which she links the consumption of products containing carrageenan with insulin resistance, but she is accused of being the only voice against carrageenan.

In fact, in 2016 a new study establishes that there are no signs of inflammation in cells exposed to carrageenan, but in the same study it is pointed out that the methodology used is only the in vitro one .

In light of this new study, it is hypothesized that the treatment of carrageenan to make it an additive, and what happens when it comes into contact with gastric juices, would cause side effects. 

Basically, one thing is seaweed, another is carrageenan used as an additive.
In fact, 3 types of carrageenan are obtained from the seaweed, which are produced by drying the seaweed and its treatment with alkalizing substances such as potassium hydroxide.

Opinions on the possible problematic nature of the processing that leads from the alga to the additive are conflicting.
However, it is good to consider that when we talk about carrageenan as an additive, we are not talking about seaweed in its natural form at all.

If we use products that contain carrageenan and suffer from problems such as intestinal swelling, irritable bowel, ulcer, it may be a good idea to try to exclude these products and see if we notice any differences.