Lactobacillus bulgaricus LB51: A Special Anti-Cancer Probiotic?

Lactobacillus bulgaricus LB51 originated from yogurt. It was first described by Dr. Ivan Bogdanov of the Laboratory for the Research and Production of Biologically Active Substances in Sofia, Bulgaria in the early 1950's. It belongs to the Lactobacillus acidophilus group of organisms and produces the D-lactic isomer of lactic acid and some amazing compounds.

This strain is deposited in the ATCC (American Type Culture Collection) as #21815. Interestingly, it is listed in the ATCC catalog as Lactobacillus leichmannii strain Tumoronecroticance 51, but is also listed as Lactobacillus bulgaricus.

What is so Special About Lactobacillus bulgaricus LB51?

L. bulgaricus LB51has some interesting anti-cancer applications. For more information on the specifics of the probiotic L. bulgaricus LB51 strain, including details of what studies have shown, look for "The L. bulgaricus LB51 Guide" in the future.

Where to Find Lactobacillus bulgaricus LB51?

In the US, Lactobacillus bulgaricus LB51 is found in Natren probiotics. Unlike many manufacturers, Natren only produces probiotics and their manufacturing practices are certified by a third-party international agency. They produce their probiotics in a pharmaceutical-grade facility and do their own culture maintenance, oil-encapsulation and freeze-drying process. Every step of the way is performed under continuous refrigeration to ensure maximum product life. The products are bottled in dark amber-glass with tin lids to prevent moisture and light from harming the products.

When you buy directly from Natren via my links, they always ship their probiotics with 2-day air shipping with blue ice and both blue ice and dry ice during hot summer months in specially-designed, thermally-controlled boxes to protect the potency. Natren does everything it can to guarantee that your probiotics will perform at their optimum levels through the expiration date on the label. That is why the links below will take you to the Natren website.

Another option for purchase in the US, Vitacost, is also listed below. Vitacost stores this product in the refrigerated section of their warehouse and will ship refrigerated probiotics with a cold pack. They recommend that you choose 1- or 2-day shipping.

Sorry, I do not have a resource for international readers.

This strain is the main product in:

Natren’s Digesta-LAC – Marketed to relieve occasional gas, irregularity and indigestion

Dairy powder, minimum 2 billion CFU per one-half teaspoon. For adults and children 2 years of age or older. Gluten-free, soy-free, non-GMO, no FOS. Contains non-fat milk and whey.

Natren Digesta-Lac has Lactobacillus bulgaricus LB51

Dairy-free capsules, minimum 2 billion CFU per capsule. Gluten-free, dairy-free, soy-free, non-GMO, no FOS. Contains garbanzo bean (chick pea) extract and potato powder, among others.

Natren Digesta-Lac has Lactobacillus bulgaricus LB51

Natren Gastro-pH – Marketed to help occasional indigestion and upset stomach

Chewable strawberry wafers, minimum of I billion CFU per 2 wafers. Contains non-fat milk, whey and less than 1 gram of fructose, among others.

Natren Gastro-pH has Lactobacillus bulgaricus LB51

Natren Healthy Tummy – Marketed to soothe your cravings for sweets while supporting digestion.

Chewable vanilla ice-cream flavored waters, minimum 1 billion CFU per wafer. Contains non-fat milk, lactose, whey, and less than 1 gram of beet fructose, among others.
Natren Healthy Tummy has Lactobacillus bulgaricus LB51

Natren Healthy TrinityClick here to read my product review.

Natren Healthy Trinity has Lactobacillus bulgaricus LB51

Is Lactobacillus bulgaricus LB51 the Probiotic for YOU?

This probiotic strain definitely has some possible interesting and beneficial properties to it. Nutritional consultations can help you determine if this supplement may be a good fit for you.

I would still recommend consuming fermented foods and drinks to give your body other sources of beneficial microbes if you decide to try this product.


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