DEAR DR. BLONZ: Are bacteria used to make buttermilk, somewhat in the same way as yogurt? Is this what gives it the sour taste? If so, is it as good for your intestinal flora as yogurt? -- S.E., El Cajon, California
DEAR S.E.: Starting as a byproduct of traditional butter-making, “buttermilk” was the name given to the liquid left after all butter was churned out of fresh dairy cream. Old-fashioned churning was not a sterile process; the milk sugar, also known as lactose, came in contact with bacteria in the air and in the nonpasteurized cream. The bacteria would use the lactose as fuel and metabolize it into lactic acid, which gave the fluid its distinctive, tangy taste.
At present, dairy companies must follow a general recipe to call a product buttermilk, but there are different types and no requirements that specific bacteria must be used. Acidophilus and bifidus bacteria are often used to make yogurt and other cultured milk products, but these are not necessarily used to make buttermilk. They may be added to the product for commercial appeal, however. Check the label or call the manufacturer to find the culturing bacteria present in the buttermilk you’re considering.
Beneficial bacteria used to make any cultured product can have a positive effect on the intestinal flora. Given the fact that they subsist on the unabsorbed remnants from foods we eat, our flora tend to reflect our general food choices. Incidentally, while the “butter” in its name gives the impression that buttermilk is a high-fat food, most commercial dairies use skim milk to make their buttermilks. An 8-ounce glass of a typical buttermilk contains 92 calories and only 2 grams of fat.
DEAR DR. BLONZ: How does psyllium compare with oat bran as a source of dietary fiber to be used as a supplement? -- F.S., Oakland, California
DEAR F.S.: Psyllium comes from the seed of the Plantago plant, a native to India and the Mediterranean. Used as a laxative in India for centuries, psyllium is also the main ingredient in over-the-counter laxatives in this country. On a weight basis, soluble fiber makes up 75 percent of the psyllium seed -- compare this to oat bran’s 8 percent soluble fiber.
Studies have shown that the addition of psyllium to the diet can help lower elevated blood cholesterol levels. Shortly after these studies were published, psyllium began to appear in commercial breads and cereals -- similar to what occurred when the same effect had been reported for oat bran. Unlike oats, though, psyllium has little to offer besides soluble fiber. Oat bran is a good source of protein, magnesium, iron, zinc, thiamine and phosphorus.
Care should be taken when adding supplemental fiber, as there can be side effects such as bloating, cramps, diarrhea and gas. In addition, loading up on fiber can interfere with the absorption of nutrients. This is a particular problem with supplements such as psyllium, which provides no nutrients of its own. Medications may also be affected, so touch base with your doctor before you add large quantities of fiber to your diet.
Oat bran might be a slight favorite as a supplement. An optimal approach to increasing one’s daily intake of fiber is to make a gradual shift to a plant-based diet with plenty of fruits, vegetables, legumes and whole grains. Here, the fiber is a natural component of foods that have much more to offer.
Send questions to: “On Nutrition,” Ed Blonz, c/o Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to firstname.lastname@example.org. Due to the volume of mail, personal replies cannot be provided.