When infants are born, both sets of teeth are concealed in their gums. Usually when they’re around 6 months old, their first teeth begin to protrude from their gums in a process known as teething. All of their teeth don’t come through at once, but for most babies all 20 of their deciduous teeth (colloquially called “baby teeth” or “milk teeth”) will have come through by their 3rd birthday.

During this time, some babies develop symptoms like irritability and disrupted sleeping. This can be frustrating and distressing for parents. While adults have the option of taking drugs for pain relief, parents generally feel understandably hesitant to pick the same solution for their babies’ discomfort. One common solution that is offered is “amber teething necklaces” – a necklace strung with beads of amber that supposedly can decrease the symptoms of teething.

Claims about how these work vary quite widely. Many sources cite completely implausible mechanisms, such as those described on Baby Amber Teething’s “About Us” page and Teething Made Easy’s “Amber Info” page:

The amazing quality of amber is ionization which helps protecting [sic] human body from various magnetic fields (amber absorbs some waves, including radioactive ones).

It is thought that amber is electromagnetic and produces large amounts of organic, natural energy

However, the most common claim I can find seems plausible. For example, here is what AmberTeethingNecklace.org’s “How Do Amber Teething Necklaces Work?” page says:

When a teething necklace made of authentic baltic amber lies against your baby’s skin, his body heat will warm the fossilized resin and allow the release of naturally-occurring succinic acid. When contact between the teething necklace and skin is maintained, succinic acid is absorbed and the healing, pain-relieving properties begin to take effect.

This claim seems to be repeated on the majority of sites selling amber teething necklaces. For example, here is what “U-GO” Products has to say on their Genuine BALTIC AMBER Teething Necklace product page:

Amber is a fossilized resin containing high levels of succinic acid, attributed for its pain relief and anti-anxiety properties.

When worn the bead warm [sic] against the skin, releasing its therapeutic properties safely and naturally.

---

Here is a simplified list of the claims involved in this explanation:

1. Baltic amber contains succinic acid
2. When worn against the skin, the amber is warmed up
3. When the amber is warmed up, it releases succinic acid
4. When the succinic acid is released, it is absorbed through the baby’s skin
5. When the succinic acid is absorbed through the baby’s skin, it relieves teething symptoms

1. Baltic amber contains succinic acid

According to Anderson et al., amber can be classified into 4 classes. The most abundant ambers are “Class I”, and amber in this class is further classified into 3 sub-classes. Baltic ambers are “Class Ia”, and “incorporate significant amounts of succinic acid into their macromolecular structure”[1]. This quality also seems to be where another name for Baltic amber, succinite is derived.

2. When worn against the skin, the amber is warmed up

This seems straightforward. Skin temperature is generally slightly above room temperature (around 32-35 °C compared with 20 °C), and apparently teething can cause a slightly elevated temperature as well[2].

3. When the amber is warmed up, it releases succinic acid

This is a bit harder to believe. The melting point of succinic acid is 188 °C[3], so it definitely isn’t seeping out of the amber in liquid form, as generally implied in the descriptions of how amber teething necklaces work. However, it is soluble in water[3] so presumably it could dissolve in sweat but considering that sweat is used in part as an excretory process this seems unlikely to be an effective method of absorbtion.

Both of these mechanisms of absorption seem unlikely, however, when the age of amber and its exposure to the elements are considered. Amber is fossilised tree resin, and the process of fossilisation. Baltic amber in particular seems to be around 34-56 million years old[4]. In order for it to still contain succinic acid after all this time, it would seem reasonable to assume that it will not yield it easily. It doesn’t seem particularly plausible to me that raising its temperature a few degrees and moistening it slightly could do what 30 million years could not.

4. When the succinic acid is released, it is absorbed through the baby’s skin

This claim strikes me as slightly bizarre after finding out that succinic acid is an irritant[3].

5. When the succinic acid is absorbed through the baby’s skin, it relieves teething symptoms

The only documented therapeutic effect of succinic acid I was able to find is an antiallergenic effect[3]. There appears to be a paper entitled The Therapeutic Action of Succinic Acid, published in 1976 by The Academy of Sciences of the USSR, but unfortunately I can’t seem to find a version of it online anywhere.

---

Many sites selling amber teething necklaces cite Robert Koch, the winner of the Nobel Prize in Physiology or Medicine in 1905 “for his investigations and discoveries in relation to tuberculosis”[5], as having analysed succinic acid in 1886, when he “confirmed its positive influence and discovered that there is no risk of the accumulation of surplus amounts of succinic acid in the human organism, even after the introduction of considerable amounts into the body.”[6]

Pretty much every mention of Robert Koch I could find on a page about amber teething necklaces used very similar wording, especially something along the lines of “positive effect on the human body”. Because of this, I think they’re all coming from essentially the same initial source, but I’ve been unable to find that.

Although the majority of sites selling amber teething necklaces cite Koch’s research on succinic acid as occuring during 1886, as far as I’ve been able to tell what this is referring to is that in 1865 he studied the secretion of succinic acid in animals fed entirely on fat, under the supervision of Georg Meissner. During this time he also self-experimented with succinic acid, apparently eating half a pound of butter each day. However, he became so sick after continuing this for 5 days that he decided to limit his study to animals. In 1866 he graduated from medical school with the findings of this study being his dissertation.[7]

His dissertation, entitled Ueber das Entstehen der Bernsteinsäure im menschlichen Organismus, was published in 1865 in a journal called Zeitschrift für rationelle Medizin[8]. I was able to find an online copy of his dissertation, in its original German, here.

I’ve read a machine translated copy, but unfortunately the machine translation is difficult to understand. It seems that the dissertation describes the appearance of succinic acid in the urine of rabbits, dogs, and humans after certain meals. Presumably this is the origin of the claim that “there is no risk of the accumulation of surplus amounts of succinic acid in the human organism, even after the introduction of considerable amounts into the body”. I haven’t been able to find the source of the claims of it having a “positive effect on the human body”.

---

In terms of how long amber necklaces are supposed to last, the information I could find tends to say that they should last indefinitely, potentially even being used across multiple generations. However, this seems incompatible with the idea that the amber works by essentially being a drug dispenser. Without an unlimited supply of the drug, succinic acid in the case, the dispenser should be expected to eventually run out and no longer be effective.

I actually managed to find one website, Teething Tots, that claimed that amber is “ideal as a natural (no drugs) homeopathic product for babies and children”. I find it quite ridiculous that a site purporting to sell homeopathic products describes the mechanism of action of this product as being precisely counter to how homeopathy supposedly works, i.e. that the active ingredient is actually present and counters symptoms, as opposed to no active ingredient being present and using an ingredient that would cause similar symptoms to those being treated.

About 3-8% of Baltic amber is succinic acid[6]. The necklaces apparently weigh around 5.5-8 g[9], which means they contain between 165 and 640 mg of succinic acid. Supposedly, this is enough to remain effective over multiple generations. In comparison, a single recommended dose of the common analgesic paracetamol for infants aged 6-24 months is 120 mg[10]. If an effective dose of succinic acid were assumed to be the same amount (I don’t mean to actually make this assumption, I’m just using it as an illustrative comparison) then an amber necklace would contain between 1.5 and 5.5 doses. Essentially about a day’s worth.

It’s not unheard of for taking a very low dose of a drug over a long period of time to have benificial effects, however. Fluoride, for example, is generally present in low levels in drinking water, and fluordating drinking water in this way is a well-documented way to reduce dental cavities. I have not been able to find any evidence, however, to support the hypothesis that chronic low dosages of succinic acid is an effective treatment for pain relief.

I have also not been able to find any evidence that supports the hypothesis that skin contact with Baltic amber is an effective treatment for the symptoms of teething. The evidence simply is not there. In fact, when searching for information on amber teething necklaces in the medical literature, the only mentions I could find were those describing it as “a quack remedy”[11][12].

Although it’s generally recommended that babies don’t wear the necklaces while unsupervised[13], various sources recommend wrapping it around their ankle while they’re sleeping.

---

I submitted a complaint to the Advertising Standards Authority regarding the advertisement on the U-GO website, which can be seen archived here – Genuine BALTIC AMBER Teething Necklace – MULTICOLOUR (as of 14 December 2010).

I have received the details of the decision but the ASA has asked me not to disclose them until they release the decision to the media. Once that has happened, you can expect to see a follow-up post here.

---

I’d like to mention that my initial interest in this topic was motivated by a post made on the Skeptoid blog by Autismum. Here’s a link to that post: The Prettiest Strangulation Device for Your Baby. She’s also written a follow-up post: Amber for Teething Update.

---

[1] Anderson, K; Winans, R; Botto, R (1992). “The nature and fate of natural resins in the geosphere—II. Identification, classification and nomenclature of resinites“. Organic Geochemistry 18 (6): 829–841. doi:10.1016/0146-6380(92)90051-X

[2] Teething Tots KidsHealth. Retrieved on 2012-12-09

[3] SUCCINIC ACID – National Library of Medicine HSDB Database Hazardous Substances Data Bank. Retrieved on 2012-12-09

[4] Fossil Amber The Virtual Fossil Museum. Retrieved on 2012-12-09

[5] The Nobel Prize in Physiology or Medicine 1905 Nobelprize.org. Retrieved on 2012-12-09

[6] Amber Information All About Amber. Retrieved on 2012-12-09

[7] Koch, Robert (1843-1910) (World of Microbiology and Immunology) Study Guide & Homework Help eNotes.com. Retrieved 2012-12-09

[8] Robert Koch Facts, information, pictures Encyclopedia.com. Retrieved on 2012-12-09

[9] amber teething necklace Huckleberry Baby Shop. Retrieved on 2012-12-09

[10] Doses change for child paracetamol medicines like Capcol – Health News NHS Choices. Retrieved 2012-12-09

[11] Taillefer, A; Casasoprana, A; Cascarigny, F; Claudet, I (2012). “Infants wearing teething necklaces“. Archives de Pédiatrie 19 (10); 1058-1064. doi:10.1016/j.arcped.2012.07.003

[12] Doherty, F (1990). “The anodyne necklace: a quack remedy and its promotion.” Medical History 34 (3); 268-293.

[13] Amber teething necklace – Keeping Kids Safe Ministry of Consumer Affairs. Retrieved on 2012-11-29