Product & Plan FAQs

Medical Conditions

What medical conditions would prohibit my use of a Medifast Program?
  • Pregnancy - Do not use the Medifast Program if you are pregnant.
  • If you have a serious acute or chronic illness (i.e., heart attack, cancer, liver disease, kidney disease, anorexia, bulimia, etc.), do not use Medifast until your health care provider says you have recovered or that your condition is stabilized.
  • We recommend you discuss your medical conditions and weight-loss plans with your health care provider before starting the Medifast Program.
  • Note: Weight-loss programs can induce rapid weight loss which may cause gallstones or gallbladder disease for those at high risk.
What medications may limit and/or prohibit my use of a Medifast Program?
  • When following a weight-loss program, talk with your health care provider about any prescription medications, especially:
    1. Diabetes medications
    2. High blood pressure medications
    3. Coumadin® (warfarin)
    4. Lithium
  • Our Thyroid Medication, Soy, and Your Medifast Plan (PDF) handout provides information on how to successfully use Medifast for individuals taking thyroid medication.
What specialized programs does Medifast offer for individuals with specific needs and preferences?
Our special programs can help you get the most out of Medifast. For more information about successfully using Medifast, please refer to our specialized program guides for: For more information about successfully using Medifast based on your specific needs, please refer to the following handouts or information: We recommend you discuss your medical conditions and weight-loss plans with your health care provider before starting the Medifast Program.
Can I use Medifast if I am currently using thyroid medication?

Our Thyroid Medication, Soy, and Your Medifast Plan (PDF) handout provides information on how to successfully use Medifast for individuals taking thyroid medication. We recommend discussing your medical conditions and weight loss plans with your health care provider before starting the Medifast Program.

If your doctor has prescribed thyroid medications like levothyroxine, Synthroid® or Levoxyl®, you should understand that eating soy may slow down your body's absorption of these drugs. You should wait one to three hours before or after taking your thyroid medication before eating any Medifast Meal containing soy protein—or choose a soy protein-free meal instead. Your healthcare provider may want to monitor your thyroid hormone levels during your weight-loss program.

For information on soy-free and soy protein-free products, please refer to our Allergen/Dietary Information (PDF).

Can I use Medifast if I have had gastric bypass surgery?

In some cases, surgery alone may not be enough for maintaining a healthy weight over the long term, and you may benefit from a nutritional meal plan to control calories. Regardless of the procedure you've undergone, Medifast can help you achieve and maintain your weight-loss goals, safely and effectively.

Please refer to our Bariatric Surgery and Medifast Information Sheet (PDF) for more information. We recommend you discuss your medical conditions and weight-loss plans with your health care provider before starting the Medifast Program. Your health care provider may want to monitor your labs and medications, or can help determine a calorie level that's appropriate for you.