• Oats
• Chia seeds
• White rice
• Ground flaxseed
• Cooked root vegetables
• Zucchini
• Eggplant

Insoluble fiber, on the other hand, is what Liebling describes as the harsh “brushy” stuff. That includes the skins and seeds of fruits and vegetables, as well as wholegrain foods like brown rice, dark leafy greens, nuts, seeds, cruciferous vegetables, and beans.

The main difference between the two types of fiber is that insoluble fiber does not dissolve in water and, because of that, triggers the intestinal muscles to work and adds “bulk and structure to stool,” explains Liebling.

In simple terms, soluble fiber helps to regulate blood sugar and cholesterol, while insoluble fiber helps to keep things moving through your digestive system.

Why is fiber so important?

Protein has been the most obsessed-over macronutrient for a while now. In 2025, though, fiber is gaining on it. According to Liebling, there are three main benefits to eating more fiber.

1. Gut health

“Fiber feeds your beneficial gut bacteria, otherwise known as the gut microbiome,” she explains. “This is like an internal control center: it regulates immunity, metabolism, brain function, and hormone balance.”

She goes on to add that adequate fiber can help, through a series of processes, to support the detoxification of excess hormones, like oestrogen, that can cause uncomfortable symptoms and painful periods.

2. Waste removal

As we know, fiber gives “bulk and structure” to your stool, something that can make going to the bathroom regularly much easier. “Fiber helps to move waste efficiently through the intestines while also absorbing and binding excess hormones, cholesterol, and toxins for safe elimination,” Liebling explains.

3. Metabolic health

Fiber plays a critical role in keeping your blood sugar steady and cholesterol levels healthy. “Soluble fiber forms a gentle gel in the gut that slows the absorption of glucose, helping to prevent sharp spikes and crashes in blood sugar that can affect energy, and trigger cravings and mood swings,” Liebling says.