Paul C, Brady DM. Comparative bioavailability and utilization of particular forms of B12 supplements with potential to mitigate B12-related genetic polymorphisms. Integr Med (Encinitas). 2017;16(1):42–49.

How common low levels are was measured by the Robert Koch Institute in a large survey: around 30 percent of adults in Germany were below 30 nmol/l, i.e. in the range of deficiency. Over 60 percent did not reach the target of 50 nmol/l. Levels were significantly lower in winter and spring than in summer.

The capsule shell

Conventional hard capsules are made from gelatin. Gelatin is obtained from the skin and bones of pigs, cattle or fish. Because gelatin is legally classified as a food and not as an additive, it does not have an E number. On the label you’ll see, for example, “capsule shell: gelatin” or “bovine gelatin”. If it just says “gelatin”, you don’t know which animal it comes from.

Schuette SA, Lashner BA, Janghorbani M. Bioavailability of magnesium diglycinate vs magnesium oxide in patients with ileal resection. JPEN J Parenter Enteral Nutr. 1994;18(5):430–435.

Terms you should look at more closely

Clegg DO, Reda DJ, Harris CL et al. Glucosamine, chondroitin sulfate, and the two in combination for painful knee osteoarthritis. N Engl J Med. 2006;354(8):795–808.

• Magnesium salts of fatty acids (E 470b), often referred to as magnesium stearate. A flow agent that prevents the powder from clumping during filling. The fatty acids can come from plants or from animal fat.
• Regulation (EC) No 1333/2008 on food additives, Annex II (list of authorised additives with E numbers).
• Shellac (E 904), a coating for tablets. It is obtained from the resin of lac insects.
• For adults, the German Nutrition Society gives estimated values of 300 milligrams (women) and 350 milligrams (men) per day. A large part of this can be covered by diet: whole grains, oats, nuts, seeds, legumes and green vegetables are good sources. A food supplement is an addition; it does not replace these foods.
• Collagen is obtained from cattle, pigs, fish or chicken. We show you how to identify the origin and why a certificate says more than “bovine collagen” on the label.
• Vitamin D3 is usually obtained from lanolin, the wool fat of sheep. A vegan alternative is produced from lichen.

Whether shellac or carmine are considered halal is not assessed uniformly. If this matters to you, ask the manufacturer or look for certification.

What the label doesn’t tell you

Flavourings are a special case. They are often dissolved in alcohol or other carrier substances. Under EU law, such carriers do not have to be listed in the ingredients if they no longer have a technological function in the finished product. For drops and liquids, it’s therefore worth specifically asking whether they contain alcohol.

The word “vegan” is helpful: a vegan product contains no gelatine, no carmine, no shellac and no animal-derived magnesium stearate. However, “vegan” says nothing about alcohol. For Muslims, a halal certificate is therefore the more reliable basis; for vegetarians and vegans, the indication “vegan” or “vegetarian” is key.

How we do it

Gelatine in capsules: Where animal ingredients hide in supplements

Sources

1. Vitamin K comes as K1 from green vegetables and as K2, which is produced by bacteria. The MK-7 form remains in the blood significantly longer than K1, as a study from the Netherlands already showed in 2007. One important note: if you are taking anticoagulant medication such as coumarins, you must talk to your doctor before taking vitamin K.
2. Regulation (EU) No 1169/2011 on the provision of food information to consumers, Article 20.
3. Regulation (EC) No 853/2004, Annex III, Section XIV (Gelatine).