What is fiber?
Fiber is a carbohydrate type that, unlike other carbs (sugar and starch), is not digested and absorbed in your gut. Instead, it passes undigested into the large bowel, where the gut bacteria completely or partially break it down. There are two types of fiber: soluble and insoluble, and they are only found in plants.
Soluble fiber absorbs water in the gut. It's found in:
- Pulses (such as beans, peas, and lentils).
- Some fruits and vegetables.
Insoluble fibers are not soluble in water. They are mainly found in:
- Wholegrains, especially the bran part of the grain.
- The seeds and skin of fruits.
Why is fiber good for your heart?
Studies have found that people who eat more fiber have lower body weight, lower blood pressure and lower cholesterol – which is beneficial for your heart health. There are a number of possible reasons for these effects:
- Fiber can help you feel fuller for longer, which helps prevent overeating. This can help you maintain a healthy weight, which is good for blood pressure, blood sugar control, and cholesterol management.
- Certain soluble fibers form a gel-like substance in the gut. This includes the fiber in oats, barley, and pulses. It helps delay or reduce certain nutrients from being absorbed into your blood, such as sugar and fats, including cholesterol.
- Some types of fiber provide food for 'good' gut bacteria. This encourages the bacteria to thrive and produce substances that are protective of heart health and can help lower cholesterol levels in the blood.
- If your diet contains a lot of fiber, it's likely that you're eating lots of plant foods that contain other important nutrients for heart health, such as vitamins, minerals, antioxidants, and plant compounds.