Brewer's Yeast

Description

Brewer's yeast is a product obtained from the yeast called Saccharomyces cerevisiae. Brewer's yeast originally was cultured in and extracted from the top layer of material in beer vats. Now, the Brewer's yeast sold as nutritional supplements in stores is produced by somewhat different processes.

Plasmolysis, the most common method for extracting yeast, was developed over 50 years ago by Vogel. In this process, salt and steam are injected into the yeast solution. The mixture is then pressed with 2 to 4% of its weight in added salt and heated to 57-67 degrees C for at least 40 hours, until the yeast component is finally separated. Because this process leaves the yeast tasting salty, some manufacturers have substituted amyl acetate or ethyl acetate with success.

Brewer's yeast is a rich source of inositol and choline, and a good source of niacin, riboflavin, pantothenic acid, thiamin, pyridoxine, folic acid, para-amino benzoic acid (PABA) and biotin. The common notion Brewer's yeast is a complete source of all the B vitamins is false. Brewer's yeast lacks vitamin B-12. The content of other B vitamins may vary between products or with the method of storage. One chemical analysis found Brewer's yeast lacked folic acid, whereas another reported it to contain appreciable amounts. Similar chemical comparisons disagree on whether any biotin is found in Brewer's yeast. Some vitamins, such as thiamin, break down during long term storage. Others B vitamins are heat labile or lose their potency upon exposure to light.

The primary trace elements in most strains of Brewer's yeast are copper and iron, with smaller amounts of chromium, manganese, nickel, tin, lead and vanadium also present. One strain, known as Brewer's yeast B also contains appreciable amounts of zinc.

Amino acids found in Brewer's yeast include: alanine, arginine, aspartic acid, glycine, leucine, lysine, histidine, tyrosine, glutamic acid, valine, and phenylalanine. Although all amino acids have been found in Brewer's yeast, cystine is clearly in shortest supply, with tryptophan and methionine also present in relatively small amounts. Depending on the yeast culture and the specific amino acid content, complementary protein combinations of Brewer's yeast with the following foods would make excellent sources of complete protein: peanuts, legumes, seeds, nuts, whole grains, corn and green leafy vegetables.

One tablespoon has 3 grams of usable protein, or about 5% of the recommended amount for adults. It may therefore be of benefit to those persons following a strict vegetarian diet and concerned with food combining. If combined with various cereal grains, Brewer's yeast can be particularly beneficial to the vegetarian.

Brewer's yeast is also a source of nucleic acid, and contains the purine bases, adenine and guanine, and the pyrimidines, cytosine and uracil.

Four carbohydrates have been purified from brewer's yeast, of which three are high molecular weight polysaccharides (glycogen, mannan, and glucan).

Differences exist in the nutritional content of various strains of Brewer's yeast. This suggests the buyer request an independent analysis of a yeast brand's nutritional profile.

Saccharomyces boulardii

Saccharomyces boulardii is an organism that belongs to the Brewer's Yeast family and is not of the group to which Candida belongs. Though not a permanent resident of the intestine, taken orally (typically in capsules containing 3 billion viable organisms) it quickly becomes established and "blooms" soon after supplementation has begun. As it blooms, it produces lactic acid and some B vitamins, and has an overall probiotic effect. S. Boulardii is eliminated shortly after supplementation is discountinued. Allergy is the most potent such formulation available.

Method of Action

Dried Brewer's yeast, when taken in adequate amounts each day, provides minerals, vitamins, amino acids and nucleic acids. Brewer's yeast has declined in popularity as a nutritional supplement, with the increased availability of less expensive synthetic sources of these nutrients.

Therapeutic Approaches

Before inexpensive B-vitamin supplements came on the market, dried yeast was recommended for the treatment of a wide variety of conditions.
Typically, daily supplementation with 4 or 5 grams of Brewer's yeast tablets was recommended.

Vitamin-fortified Brewer's yeast tablets were developed in the early 1940's to ensure the yeast supplement was balanced. These tablets were fortified with the then newly synthesized thiamin and vitamin B-6. In more recent years "high-chromium Brewer's yeast" have been marketed. Recently, however, chromium picolinate has replaced "high-chromium Brewer's yeast" as the chromium supplement of choice.

Between 1920 and the late 1940's, Brewer's yeast was used in the treatment of the following conditions:

Condition	Suspected vitamin deficiency
anorexia	thiamin
peripheral neuropathies	thiamin
polyneuritis of pregnancy	thiamin
glossitis	riboflavin
stomatitis	riboflavin
dermatosis	riboflavin
ocular lesions, esp. corneal degeneration	riboflavin
anemia	folic acid

B-complex is well known for its vitalizing effects. Consequently, it is used in treating diseases which produce fatigue, including Chronic Fatigue Syndrome, stress and cancers. However, the view has been expressed that it is contra-indicated in osteoporosis, while increased knowledge about specific metabolic pathways encourages the use of specific vitamins, notably pyridoxine, folic acid and the various forms of niacin, rather than as a complex.

Nothing is ever simple, so the opposing view, that the B vitamins belong together in a delicate balance cannot be disproved. The middle ground is to take a specific supplement at a higher dosage, together with the whole complex.

Atherosclerosis

In recent years several studies have looked at the ability of chromium-enriched Brewer's yeast to lower LDL-cholesterol, while raising HDL-cholesterol.

In one study, 46 healthy volunteers were classified as either normolipidemic or hyperlipidemic and supplemented with chromium-enriched Brewer's yeast. After 8 weeks, triglyercides were unchanged but serum cholesterol was reduced for 8 of 15 of the hyperlipidemic subjects and 10 of the 11 normolipidemic subjects. HDL also increased for both groups.

In a second study conducted single-blind, 24 elderly patients were given chromium-enriched brewer's yeast for 8 weeks. They were found to have improved glucose tolerance and decreased serum cholesterol.

This was particularly found in the four hypercholesterolemic patients. Interestingly, those subjects on the chromium-poor torula yeast had no change in total lipids or cholesterol.

In a third study, subjects received 7 grams of chromium-enriched Brewer's yeast (providing 15 micrograms of chromium). After only 6 weeks there was a significant increase in HDL-cholesterol levels, and improvement in HDL to LDL ratios.

Turner's syndrome

A study investigated the effect of Brewer's yeast supplementation on patients with Turner's syndrome. Patients were given 50 micrograms of chromium by ingesting 30 grams of Brewer's yeast daily. The glucose area index total in 5 of 8 patients was decreased, presumably due to the chromium supplementation obtained from the Brewer's yeast.

Brewer's yeast and a special strain (Hansen CBS 5926) are approved as herbs by the German Commisssion E.

Brewer's yeast is used for loss of appetite (see appettie disorders) and as a supplement for chroniuc forms of acne and furunculosis.

Hansen's is recommended for the symptomatic treatment of acute diarrhea.

References:

Blumenthal, M (Ed.): The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. American Botanical Council. Austin, TX. 1998.

Toxicity Factors

No toxicity has been reported from the use of Brewer's yeast.

Sensitive individuals may suffer migraine headaches.

Brewer's yeast has approval status by the German Commission E.

Average daily dosage in Germany is 6 g.

The German Commission E warns against an increase in blood pressure (i.e. hypertension) with the simultaneous administration of brewer's yeast and MAO inhibitors.

The presence of antimycotics (antifungal drugs) can also affect the activity of brewer's yeast.

References:

Blumenthal, M (Ed.): The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. American Botanical Council. Austin, TX. 1998.

References

Blumenthal, M (Ed.): The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. American Botanical Council. Austin, TX. 1998.

Bruguerolle-B; Roucoules-X: Time-dependent changes in body temperature rhythm induced in rats by brewer's yeast injection. Chronobiol-Int. 1994 Jun; 11(3): 180-6.

Eddy, A.A. Aspects of the chemical composition of yeast. The Chemistry and Biology of Yeasts. Academic Press, N.Y. 1958, pp. 157-240.

Elwood, J.C. et al. Effect of high-chromium brewer's yeast on human serum lipids. J Am Coll Nutr., 1982: 1; 263-274.

Hamilton, E.M.N., E.N. Whitney & F.S. Sizer. Nutrition - Concepts and Controversies. West Publishing, San Francisco. 1985. p. 142.

Li-YC: Effects of brewer's yeast on glucose tolerance and serum lipids in Chinese adults. Biol-Trace-Elem-Res. 1994 Jun; 41(3): 341-7

Offenbacher, E.G. & F.X. Pi-Sunyer. Beneficial effect of chromium-rich yeast on glucose tolerance and blood lipids in elderly subjects. Diabetes, 1980: 29; 919-925.

Pike, M. The technology of yeast. In: The Chemistry and Biology of Yeasts. Academic Press: New York, 1958, p. 562.

Riales, R. Chromium in Nutrition and Metabolism. North-Holland Biomedical Press, Amsterdam. 1979. pp. 199-212.

Saner, G., V. Yuzbasiyan, O. Neyzi, H. Gunoz, N. Saka & S. Cigdem. Alteration of chromium metabolism and effet of chromium supplementation in Turner's syndrome patients. Am J Clin Nutr. 1983. 38; 574-578.

Schellenberg-D et al: Treatment of Clostridium difficile diarrhoea with brewer's yeast [letter]. Lancet. 1994 Jan 15; 343(8890): 171-2

Schrauzer-GN; de-Vroey-E: Effects of nutritional lithium supplementation on mood. Biol-Trace-Elem-Res. 1994 Jan; 40(1): 89-101.

Yoshikawa-K et al: Classification of some alpha-glucosidases and alpha-xylosidases on the basis of substrate specificity.. Biosci-Biotechnol-Biochem. 1994 Aug; 58(8): 1392-8.