- With Mayo Clinic nutritionist
Katherine Zeratsky, R.D., L.D.
read biographyclose windowBiography of
Katherine Zeratsky, R.D., L.D.
Katherine Zeratsky, R.D., L.D.
As a specialty editor for the Food & Nutrition Center, Katherine Zeratsky helps you sort through the facts and figures, the fads and the hype to learn more about nutrition and diet.
A Marinette, Wis., native, she is certified in dietetics by the state of Minnesota and the American Dietetic Association. She has been with Mayo Clinic since 1999.
She is active in nutrition-related curriculum and course development in pediatrics at Mayo Clinic Rochester and nutrition education related to the physiology and recommended intakes for premature infants.
Other areas of interest include breast milk and formula safety, neonatal feeding, and nutrition for breast-feeding mothers.
She graduated from the University of Wisconsin-Madison, served a dietetic internship at the University of Iowa Hospitals and Clinics, and worked as a registered dietitian and health risk counselor at ThedaCare of Appleton, Wis., before joining the Mayo Clinic staff.
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Question
CortiSlim: Do cortisol blockers increase weight loss?
Can cortisol blockers such as CortiSlim help me lose weight?
Answer
from Katherine Zeratsky, R.D., L.D.
There is no reliable evidence that so-called cortisol blockers such as CortiSlim, CortiStress and Cortistat-PS will lead to weight loss.
Until recently, the manufacturers of cortisol blockers claimed that high levels of stress increase your body's production of the hormone cortisol supposedly to the point that causes you to accumulate excess fat. But what they didn't tell you is that this occurs only when your body produces large amounts of cortisol due to a side effect of medication or due to an underlying medical condition such as Cushing's syndrome. There's no evidence that the increased cortisol produced by a healthy individual under stress is enough to cause weight gain. Also, there's no evidence that the ingredients in these products — mixtures of vitamins and herbs — even block cortisol or that blocking cortisol results in weight loss.
In fact, in 2007 the Federal Trade Commission charged the marketers of CortiSlim and CortiStress with making false and unsubstantiated claims that their products can cause weight loss. As part of the resulting settlement, the companies were forced to pay millions of dollars in consumer refunds and are no longer allowed to make weight-loss claims.
Bottom line: The most effective way to lose weight is to control calorie intake and increase the number of calories burned through activity and exercise. There is no "magic diet pill" that can peel off the pounds for you.
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