Want B12, But Hate Meat? Drink Milk! SNAC-Fortified Cyanocobalamin 136% More Bioavailable Than Standard B12 - Still Less Effective Than B12 From Cow's Milk

Figure 1: Milk still rules the
world (of B12 supplements ;-)

Vitamin B12 deficiency is probably more prevalent, than many people would have it. The water-soluble vitamin is most abundant in foods of animal origin and vegetarians (let alone vegans) are as much at risk of having inadequate B12 levels, as people with achlorhydria and, consequently, low intrinsic factor (an enzyme that requires an acidic environment to function and facilitate the utilization of B12 from foodstuff), or more generalized disturbances of the gastrointestinal structure due to aging (food-cobalamin malabsorption becomes increasingly prevalent after the age of 50), gastric resection, ileal resection, Crohn's disease, and bacterial overgrowth of the intestine. With vitamin B12 deficiency affecting cell division and precipitating to megaloblastic anaemia and neuropathy, close monitoring not only of vitamin B12 intake, but also of its proper utilization is of utmost importance for people belonging to one of the aforementioned groups.

Scientists from Emisphere Technologies in Cedar Knolls, New Jersey, have now come up with a new cyanocobalamin/SNAC coformulation, in which the sodium caprylic acid salt, N-[8-(2-hydroxybenzoyl)amino]caprylate (SNAC), a proven drug delivery agent, shall facilitate a more pronounced and more reliable absorption of orally supplemented vitamin B12 (Castelli. 2011). The formula, which contained 5-mg cyanocobalamin and 100-mg SNAC was administered to 6 human subjects in the fasted state in the form of 1 tablet, which had to be taken with 50 mL of water. Blood samples were taken at staggered intervals with the last blood draw taking place 24h after the ingestion of the B12/SNAC coformulation.

Figure 1: Time to and maximal serum concentration of B12 after oral administration or infusion of cyanocobalamine with and without SNAC; note: in order to compensate for the major differences between oral cyonocobalamine with and without SNAC a logarithmic scale was used (data adapted from Castelli. 2011).

As expected the concomitant administration of sodium N-[8-(2-hydroxybenzoyl)amino]caprylate (SNAC) increased the meager biovalability of cyanocobalamine (which is absorbed really poorly, anyway) significantly:

Absolute bioavailability of B12 with the SNAC formulation was calculated from non–baseline-adjusted data to be 5.09% and was significantly greater (P < 0.05) than the commercial formulation (2.16%).

In view of the recently elucidated bioavailability of natural B12 from plain cow's milk (Matte. 2011), or should I say "liquid white gold", the 136% increase in bioavailability Christina Castelli and her coworkers achieved with their artificial combination of B12+SNAC appear quite ludicrous. 8%-10% that is the bioavailability et al. report in Jacques Matte and his colleagues from Canada report in their study on the bioavailability of vitamin B12 from cow's milk. Granted, this is a pig model, but other than rodents, which are usually used when it comes to studies, in which surgical interventions are necessary to elucidate the exact pharmacodynamics of a specific drug, pigs provide a very adequate model for the human gastrointestinal system, or as Miller and Ullrey already stated it in a 1987 paper on the "The Pig as an Animal Model For Human Nutrition" (Miller. 1987)

[...]with the possible exception of nonhuman primates, it is apparent that the omnivorous pig is one of the best models for study of nutrition issues in the omnivorous human.

This long established adequacy of the pig model of the human gastrointestinal tract has only recently been confirmed by Goulloteau et al. (Guilloteau. 2010). Matte et al.'s result that vitamin B12, which is naturally and abundantly present in cows’ milk, is more available at the intestinal level than the synthetic form - even if the latter is supplemented with SNAC - are thus very likely to apply to humans, as well.

Figure 2: Pharmacokinetics of vitamin B12 from different sources measured in pigs with an ultrasonic flow probe around the portal vein and a catheter inside the portal vein; values expressed as differences vs. unsupplemented animals; both values for cyanocobalamine alone are effectively 0, i.e not different from unsupplemented pigs (data adapted from Matte. 2011).

These results are also in accordance with retrospective studies in human subjects showing that vitamin B12 status is highly correlated with dairy product intake and studies on the absorption (absorption = entering the cells vs. bioavailability = becoming available in the blood stream) of vitamin B12 from dairy products in older men and women (>60y) by Robert M. Russel et al. (Russel. 2001), who report absorption of up to 65% for milk, which would be almost identical to the generally accepted absorption coefficient for meat products.

Note: Using a pig model Matte et al. were able to actually measure the portal-drained viscera (PDV) flux of vitamin B12, which provides more reliable results than radio-labelling studies, as they were used in Russel et al. It is thus all the more intriguing that the PDV for the unsupplemented diet or cyanocobalamin supplements [...] were not different from 0", or in other words - providing pigs with cyanocobalamine, which is the form of vitamin B12 that is used in most common dietary supplements, had no effect  on serum B12 concentrations, at all.

So, what does this tell you, after all? Well, let me phase it like that: If you have a Ferrari Enzo (milk and meat) waiting for you at the front door (in the fridge), wouldn't it be plain-out stupid to try to chip-tune (add SNAC) the family car (cyanocobalamine)? An the moral of the Story? Eat, don't supplement your vitamins!

Green Tea Inhibits Fat Gain, But Will It Also Hinder Muscle Gain? Decreased Protein Absorption in Rats Supplemented With Green Tea Extract

It has gotten relatively quiet around green tea within the past weeks. Everybody knows about its anti-oxidant effects, its modest efficacy as a weight loss supplement and the relaxing effect of taking a time-out from the stressors of daily life with a good cup of freshly brewed tea. Now, scientists from Poland (Bajerska. 2011) found another interesting, yet not so beneficial property of green tea extract.

The scientists fed laboratory rats on a high fat diet chow with either 0%, 1.1% or 2.2% of green tea extract [GTAE] added and found that only the chow containing 2.0% GTAE had significant effects on body weight gain (5.6% less than control) and visceral fat accumulation (-17.8% vs. control). Yet, they observed a

[...] considerably (P < .05), reduction in the digestion of protein (but not fat) was observed in both GTAE groups (1.1% GTAE: 82.6% ± 1.8%; 2.0% GTAE: 84.3% ± 0.8%) when compared to the control (93.3% ± 1.5%).

This novel finding appears to stand in line with previous studies, in which green tea supplementation decreased fat absorption in the intestine. Interestingly, this effect was absent / non-significant in the current study (cf. figure 1).

Figure 1: Daily food intake, FER, apparent digestion of protein and fat, energy value of feces, and visceral fat content of treatment and control groups (Bajerska. 2011)

These findings have yet to be put into perspective, in order to assess how significant these results are for you, as a potential consumer of green tea supplements. Do you have to increase your protein intake if you consume one or two caps of green tea extract or the occasional cup of freshly brewed tea? Probably not. The rats in the study consumed 11g/kg, respectively, 20g/kg body weight of the extract. For a 80kg human being this would be a daily GTAE consumption of roughly 260g. Personally, even a teaspoon of GTAE makes me nauseous within minutes, so I guess none of you will even come close to this (over-)dose of supplemental green tea.

It is also noteworthy that, in view of the dose-response relationship between the amount of extract the rats consumed and its effect on their body weight, these results do also indicate that the amounts of GTAE you usually find in so-called "fat burners" will hardly have any direct effect on your body weight or fat, no matter what the respective supplement companies are telling you.