The Immune Disorder That Made HGTV's Heather Rae El Moussa Dread Filming

When former "Selling Sunset" star Heather Rae El Moussa first began experiencing such intense physical and mental fatigue that she couldn't get out of bed, she and her husband, "Flip or Flop" star Tarek El Moussa, blamed her postpartum "mom brain." However, once her exhaustion started affecting her ability to produce milk for her newborn son, Tristan, El Moussa knew she had to see a doctor.

El Moussa opened up about the harrowing experience to Today, describing how she "was exhausted all the time and no amount of sleep could make it better. Filming was absolutely brutal." And as the bloodwork results from her doctor's appointment revealed, El Moussa wasn't experiencing run-of-the-mill brain fog. She was suffering from Hashimoto's disease, an autoimmune thyroid disorder that affects only 1-2% of the U.S. population.

"When [the doctor] told me what I had, I was in total shock," El Moussa recalled. Although the HGTV personality said her condition has improved since starting synthetic hormone therapy, her diagnosis was one item on a long list of challenges she faced as a brand-new mom.

Heather Rae El Moussa felt 'dead' before she received her diagnosis

Hashimoto's disease originates in the thyroid gland in the lower neck and affects the body's ability to produce hormones essential for proper body functioning. Symptoms of the condition can include intense fatigue, weight gain, thinning hair, joint pain, and constipation. If left untreated, the chronic inflammation disease can permanently damage the thyroid. The causes of this disease are largely unknown, although research has found Hashimoto's disease is more prevalent in women than men, per MedlinePlus.

"The Flipping El Moussas" star Heather Rae El Moussa's first indication something was wrong was Hashimoto's disease's most prevalent symptom: exhaustion. "I remember saying to my assistant, 'I feel like I'm dead,'" El Moussa recalled to Today. This made it difficult for El Moussa not only to continue her professional career as a model and TV personality but also to take care of herself and her newborn son.

"I was like, I'm probably just foggy because of mom brain," she continued. But it was a dramatic decrease in her milk supply — from six ounces per day to barely half an ounce — that caused her lactation specialists to recommend she visit a doctor. Following her diagnosis, El Moussa was prescribed a synthetic hormone called levothyroxine that functions like the T-4 hormone typically produced by the thyroid. The HGTV star said the medication has her "feeling much better."

Heather Rae El Moussa had a lot working against her breastfeeding journey

In addition to working through her Hashimoto's disease diagnosis, Heather Rae El Moussa's newborn son had difficulty breastfeeding due to a tongue tie, cheek tie, lip tie, and jaundice. The TV star wrote about her lactation journey in a February 2023 Instagram post, explaining that her son's inability to latch was causing him to lose weight significantly. "I had many tearful nights in the beginning because I'd be up at 3 a.m. trying to feed him and felt so defeated," she wrote.

El Moussa told Today that the 4-month-old had a tongue-tie laser surgery that remedied his inability to latch properly. That, in addition to El Moussa's lactation specialists, hydration-focused meal plan, and her treatment for Hashimoto's disease, have turned her and her son's breastfeeding journey around. 

"We had a lot of things working against us," she told Today, "including my autoimmune disorder, but we did it. I've heard so many women say, 'I only breastfed two months,' and that makes me feel sad. Why 'only?' You should feel so proud that you even did it at all!" Both El Moussa and her son Tristan seem to be doing much better these days. In a July 2023 Instagram post, El Moussa wrote that her young son is "so curious, happy, cuddly, and chill. Your zen soul is beautiful, and the world is a better place because of your kind heart."