For the first few days after giving birth (before real milk appears), a woman’s breast produces colostrum, a yellowish fluid that’s low in fat but high in nutritional value. Full of white blood cells and antibodies, colostrum also coats the newborn’s gastrointestinal tract, helping with digestion. Now health fanatics are supplementing their diets with colostrum from cows, hoping to reap the same benefits as the human stuff to help with everything from anti-aging to weight loss.

To understand how bovine colostrum (also called symbiotics, because they support probiotics in optimizing digestive health) works for weight loss, we turned to LivingHealthy expert Ashley Koff, RD.

“When we talk about better nutrition to achieve any health goal, especially weight loss, I use the mantra: ‘You are not what you eat, you are what you digest and absorb,’” says Koff, a regular guest expert on Fox 5 DC who also frequently appears on The Dr. Oz ShowThe Today Show and The Doctors.

According to Koff, stress (from environmental toxins to sleep deprivation) can lead to digestion issues that slow down weight loss—even if your diet is optimal. “One reason we continue to see so many people struggle with achieving and sustaining healthy weight loss—despite valiant efforts to eat right and exercise—is that their digestion is not functioning optimally,” Koff explains. “Just because the right nutrients go into your body as foods doesn’t mean they end up where they are needed and arrive in the usable forms.

To help repair digestion problems, Koff touts the benefits of colostrum: “Also called ‘liquid gold,’ colostrum is the first milk that comes in,” she says “Colostrum transfers immune enhancing nutrients from mother to child—part of those go toward building that healthy foundation of the digestive system.”

Like runs in a pair of pantyhose, wear and tear on the digestive tract lining can produce holes (known as “leaky gut”) that not only threaten the survival of probiotics (healthy bacteria that should be in residence throughout the digestive tract), but also allow other key nutrients to escape or not get absorbed properly. According to Koff, bovine colostrum helps to repair and maintain a healthy digestive tract lining, so probiotics can thrive, nutrients can be absorbed and toxins can be identified for removal.

Why are we tapping into bovine colostrum, instead of goat or sheep? Because cows have a more complex gut (4 stomachs), the calf is actually born without a fully formed digestive tract. That’s why bovine colostrum contains more growth factors than the human variety, which can help humans maintain healthy digestive tracts in the long run. “On a quality dairy farm in the United States or New Zealand, where the cows are grass-fed and antibiotic-free, they make a ton of colostrum, much more than humans, and have a lot left over after they feed their calves,” adds Koff. Historically, all this extra bovine colostrum went to waste, but these days more dairies have started capturing it as a supplemental food. However, it’s important to note that all colostrum is not created equal. Not all companies use the first milkings (actual colostrum) and the health of the mother cows is a key factor in the nutritional value of the colostrum itself.

So whether your personal health goals are weight loss (or maintenance) or body composition improvement, consider the impact that optimizing your digestion will have on your results. And to improve your digestive health, try pairing your probiotics with their new best friend: bovine colostrum.