Yom Kippur, the Day of Atonement and holiest day of the year for the Jewish people, begins Friday evening.
The holiday, dedicated to introspection, prayer and asking God for forgiveness for the past year's transgressions, includes 25 hours of fasting.
While fasting is an important part of the holiday, health plays a central role in whether to fast and how to approach it. According to the Talmud, the primary source of Jewish law, a person's health must take precedence over fasting. For instance, if an individual or their physician believes fasting puts their health at risk, it is acceptable to forego fasting.
There are certain conditions where fasting is not recommended, such as women who are pregnant or breastfeeding, said Dr. Beth Widen, a Shaker Heights native and assistant professor of Nutritional Sciences at The University of Texas at Austin.
Fasting is risky for both mom and baby during pregnancy, because extended fasting causes ketosis, a metabolic state in which carb intake and insulin levels are low, Widen said. This is risky for the baby, potentially impairing brain development and causing birth defects, she added.
During breastfeeding, a short period of fasting will not greatly impact the amount of milk produced or its nutrients. But a large amount of energy and water are needed daily for milk production, so breastfeeding people often are excused from fasting, Widen said.
Other conditions where fasting might be problematic include diabetes or any sort of chronic illness where an individual might be taking medications that could cause dizziness or that require food to consume, Widen said. Diabetes management requires regular intake of carbohydrates, along with medications, so fasting would lead to low blood glucose or hypoglycemia, which can cause headaches, irregular or fast heartbeat, dizziness or lightheadedness.
Widen recommended checking with a health care provider before fasting.
For those who do decide to fast, doing so begins with proper planning, said Bruce Sherman, an exercise physiologist based in Shaker Heights.
“The best recommendation is just have a day of moderation and eating the day before, and a couple of days before with caffeine," he said. "Just avoid salty foods, eat complex carbohydrates and drink plenty of water.”
Taking these steps will reduce the chances of dehydration, thirst, headaches from caffeine withdrawal and feelings of hunger, he said.
Widen agreed that planning ahead and eating in moderation is an important part of fasting.
"Focus on nutrient-dense foods and eat well in the days before the fast, so you are satisfied before beginning fasting," she said. "This includes making sure you eat enough protein, a variety of fruits and vegetables, and other foods you enjoy and that are nourishing. Also, it is important to avoid overeating. Eating too much before fasting might make you uncomfortably full."
A healthy approach to the holiday also includes some light physical activity during the fast, Sherman said.
"One little thing that can help you kind of get through those hard periods is introduce just a little bit of activity into your day," he said. "It is better to have a little activity — go for a walk when you have a break from going to synagogue. That is actually good for somebody who is fasting rather than just sitting around and doing nothing. That act of exercising will probably release some sugars into the system for the body to nourish the musculature and the brain."
Healthy fasting also involves taking action should there be signs of problems, Widen said.
"Listen to your body," she said. "If you start to get dizzy or feel terrible, have some water or some juice and see if that helps."
Once the fast is over, it is important to rehydrate by drinking water, Sherman said.
“Just make sure you get some fluid in the systems that have been deprived, your cardiovascular system, your kidneys. They all need to get back on their normal level of hydration and fluid processing, and that’s a good way to jumpstart it," he said.
Yom Kippur ends at sundown on Oct. 12.
