If you know about using cranberry juice to treat a urinary tract infection
(UTI), then you should also know that it is mannose in the cranberries that
makes it work so well, and you can get it from other sources too. Urinary
tract infections can be very painful or uncomfortable. The symptoms
include painful urination, urgent need to urinate, and foul-smelling urine. For
some people, especially women, it can feel like a recurring nightmare.
D-mannose is a naturally occurring simple sugar that can increase your
healthy bacteria and improve your gut health, all without increasing your
blood sugar. Even though D-mannose is considered a simple sugar and a
glucose, it has several important differences. It is lower on the glycemic
index, which means it does not immediately turn into glucose and does not
have the negative effect on insulin and blood sugar levels.
D-mannose is absorbed in the gastrointestinal tract more slowly. Another important difference
is the kidneys filter D-mannose out of the body rather than allowing it to be
stored in the liver like glucose.
D-mannose occurs naturally in microbes, plants, and animals, and it is
found in abundance in some foods. It is considered a prebiotic because
consuming D-mannose in any form stimulates the growth of good bacteria
in your gut. The D in D-mannose refers to the supplement form, whether
powder or capsules. When it occurs naturally, it is mannose.
Mannose is found in high quantities in several fruits and vegetables. If UTI
is a problem for you, it is easy to fit any of these foods into your diet.
• cranberries (and cranberry juice)
• apples
• oranges
• mangos
• peaches
• broccoli
• green beans
• tomatoes
• eggplant
• cabbage
• fenugreek seeds
• kidney beans
• turnips
• cayenne pepper
• aloe vera
• seaweed
The biggest benefit of D-Mannose is its ability to stop certain bacteria from
growing in the urinary tract. Researchers believe 90% of UTI’s are a direct
result of E. coli bacteria that enter the urinary tract. Once there, they latch
on to the cells, multiply, and cause a urinary tract infection. When you eat
foods or supplements containing D-mannose, your body eliminates it
through the kidneys and into the urinary tract. This elimination into the
urinary tract and flushing out of the body stops the E. coli bacteria from
latching on and prevents an infection.
When To Use D-Mannose
There are two types of people who use D-Mannose: people who get
recurring UTI’s, and someone with an active infection. The dosage and
type of D-mannose you use will be different.
D-Mannose is promising for people with recurring UTI’s. Many women are
given a low dose round of antibiotics every six months to a year to prevent
reoccurrence. Unfortunately, this can cause the bacteria to become
resistant to the antibiotics, in addition to the harm antibiotics cause to the
gut.
A pilot study conducted at the Department of Gynecological
Obstetrics and Urologic Sciences of "Sapienza" University of Rome,
concluded that D-mannose showed significant improvement in symptoms
for women with recurring UTI. In another study of 98 people, one group
was given Nitrofurantoin, a common drug for prevention and treatment of
UTI. The results of the study showed no difference in those who took D-mannose
and those who took Nitrofurantoin. This is important for people
who prefer taking natural remedies for recurring UTIs without compromising
their gut health.
A 2016 study found evidence that D-mannose is effective at treating active
UTIs as well.
Dosage
According to research, scientists found the following dosages to be most
effective:
• For preventing frequent UTIs: 2 grams once daily, or 1 gram twice
daily
• For treating an active UTI: 1.5 grams twice daily for 3 days, and then
once daily for 10 days; or 1 gram three times daily for 14 days
You can get D-mannose in several ways, through your food, capsules, or
powders. If you don’t like taking capsules, or are already taking too many,
you may opt for getting D-mannose in certain foods or in powder form,
mixed with water.
Risks and Side Effects
None of the studies cited found side effects significant enough to stop
treatment. The only side effect mentioned was mild cases of diarrhea,
which the participants chose to tolerate in exchange for relief of UTI
symptoms. Patients who are pregnant or diabetic should consult their
health care provider before taking this or any supplement.
LaVera J. Forbes, PhD, MS, CHN, is the founder of Dr. LaVera’s Healthy Aging, LLC. Find free healthy aging resources at drlavera.com.
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