Tanya’s kosher workouts and 90-calorie challah

Most of the clients who visit Tanya Rosen, a Brooklyn-based nutritionist specializing in weight loss, are Orthodox Jews like herself. Nutrition By Tanya operates five branches — in Monsey, Williamsburg, Flatbush, Borough Park and Lakewood — and plans to open three more locations in coming weeks. She also operates a fitness studio in Brooklyn.

Rosen, 35, said she’s helped “probably close to 10,000″ clients lose weight.

Observant Jews, Rosen noted, face a unique set of weight loss challenges, including a steady rotation of Shabbat and holiday meals, rules dictating modest dress that can make going to the gym uncomfortable, as well as a high rate of pregnancy among women.

Today, there is increased interest in healthy eating in the Orthodox community, said Mendel Singer, an associate professor of epidemiology and biostatistics at Case Western Reserve University in Cleveland who has studied obesity in Jewish day schools. Singer found that children at Orthodox day schools in the Cleveland area — and especially haredi Orthodox ones — were more likely to be obese than their counterparts at non-Orthodox schools.

“There’s a trend towards more exposure to these topics about eating healthier,” he told JTA, citing an increase in kosher cookbooks and articles in Jewish publications focusing on a balanced diet. More conversation around the topic of healthy eating can “help people to realize that it is an issue to be sensitive to.”

Rosen’s expanding business is a testament to that trend. She recently introduced “Tanya-approved” health-conscious menus in four kosher restaurants in Brooklyn and Monsey.

As part of the services she offers, Rosen makes personalized six-week menus for clients — including meals designed for Shabbat and Jewish holidays — so they know exactly what and how much to eat. The schedule provides three to four choices for each meal, such as chicken and rice, fish and baked potato, and whole wheat wrap with tuna and vegetables. Clients then visit one of the offices on a weekly basis to be weighed, review the plan, and discuss challenges and possible changes.

Additionally, Rosen sells a line of prepared kosher diet food products — known as “Tanya Approved Products,” or TAP, including muffins, soups and portion-controlled, 90-calorie challah rolls —at her Nutrition By Tanya locations.

Rosen’s women-only fitness studio, Shape Fitness, in Midwood, offers such classes such as Pilates, kickboxing and zumba, as well as personal training.

For those who prefer working out at home, she also sells “kosher” exercise videos featuring covered-up instructors and instrumental music (to avoid suggestive lyrics).

Rosen’s nutrition counselors are Orthodox Jews, so they can “really relate to the [clients’] lifestyle and the struggles,” she said.

The mother of four attributes her success to a lot of hard work — Rosen described her schedule as “a little beyond full time.” Her workday goes from 7 am to about midnight, with a break in the evening to spend time with her family. She said she’s always reachable via text to answer her clients’ questions, such as which product to buy in the grocery store or what to order at a restaurant.

“I’m probably never just relaxing,” she said.

Though Rosen declined to give a success rate, she said that anyone who follows her plan, with the exception of those with a medical condition requiring treatment by a doctor, “does well and loses weight.”

Should clients need extra inspiration, all they need to do is look at Rosen. She embarked on a weight loss journey after her first pregnancy in 2004. As Rosen shed 40 pounds she gained a newfound interest, which led her to enroll in a master’s program in nutrition and ultimately launch her business.

Rosen said the positive effects she has seen in clients’ lives, such as increased confidence and better work productivity, keep her motivated to continue her busy lifestyle.

“Even the worst day is a good day,” she said.