This article was originally written by the Sequence clinic team (now known as WeightWatchers Clinic).
In this article:
1/ How much fiber do you need?
2/ What are the different types of fiber?
3/ What are the health benefits of increasing fiber intake?
4/ How to increase fiber intake
When looking at your overall diet, you probably focus on the big guys: calories, protein, fat, added sugar. But what about fiber? It may not be the sexiest of nutrients, but eating enough fiber can help improve your health, keep your GI system humming, and even give you a leg up in managing your weight. Here’s more about fiber’s health benefits, how much you really need, and how to incorporate more into your day.
How much fiber do you need?
There’s a big difference between how much fiber you should be eating and how much you probably are eating. The USDA recommends women eat 22 to 28 grams a day, depending on their age, while men should get 28 to 34 grams daily. But the average American adult is only getting around 16 grams of fiber a day, well below even the low end of the recommended ranges. Curious where you land? WeightWatchers members can see how much fiber they get in a day by checking My Day on the app.
What are the different types of fiber?
Fiber is a type of carbohydrate that the body cannot digest. The two main types of fiber are soluble fiber and insoluble fiber.
- Soluble fibers dissolve in water and become a gel-like substance. Through this process, they help slow down digestion, so you stay full longer. They can also impact how much cholesterol is absorbed by the body, helping lower levels and improve heart health.
- Insoluble fibers do not dissolve in water. They provide bulk to your stool, helping promote regular bowel movements and prevent constipation.
Foods high in fiber — like vegetables, fruits, nuts, seeds, beans, legumes, and whole grains — typically contain a combination of both soluble and insoluble fiber.
What are the health benefits of increasing fiber intake?
Consuming the recommended amount of dietary fiber can help reduce your risk for various health conditions, including:
- Coronary artery disease
- Stroke
- Hypertension
- Diabetes
- Gastrointestinal disorders
- Obesity
Here’s more about how it can do all of that.
How does fiber improve your heart health?
To understand the role fiber plays in reducing the risk of heart diseases, strokes, and other vascular diseases, it’s important to understand how these diseases develop over time.
LDL cholesterol can build up in your arteries, raising your risk for heart disease. In contrast, HDL cholesterol (sometimes called “good” cholesterol) is protective of heart health as it carries LDL cholesterol back to the liver where it can be removed from the body.
Soluble fiber reduces your LDL levels. It does this through a slightly complicated process. It binds to bile acids in your small intestine and removes them from your body in your stool. Due to the reduced amount of bile acids available, your liver will pull LDL cholesterol from your blood to make new bile acids, thereby decreasing levels of cholesterol. Fiber also helps reduce LDL levels by producing a type of fatty acid that inhibits the activity of an enzyme needed to make cholesterol, thus lowering cholesterol production.
How does fiber help control blood sugar?
When soluble fibers form that gel-like substance in the small intestine, it decreases how quickly the body breaks down carbohydrates into glucose. This leads to a lower glucose response after meals (in other words, less of a spike in blood sugar) and, as a result, your body produces lower levels of insulin.
Studies evaluating the effects of increasing dietary fiber by 10 grams per day in individuals with type 2 diabetes showed improvements in hemoglobin A1c — a three-month average of blood sugar levels — as well as improvements in fasting blood sugar and insulin sensitivity.
What is the role of fiber in gut health?
A healthy gut microbiome is important for mental health, immunity, gastrointestinal health, disease prevention, and more. Fiber plays a crucial role in promoting a healthy gut microbiome — especially some insoluble fibers called prebiotics. These help feed the gut bacteria so they can flourish. This is why there is increasing evidence that diets higher in fiber are linked to a more diverse microbiome.
Fiber may also help prevent or improve gastrointestinal disorders like diverticular disease, hemorrhoids, and irritable bowel syndrome (IBS). Research has shown improvements in IBS symptoms among patients supplementing with certain fibers like psyllium.
How does increasing fiber help you manage your weight?
Increased soluble fiber intake has been associated with lower body weight and belly fat. One reason why is that high-fiber foods are more satiating, or filling. In clinical trials, high-fiber meals resulted in decreased food intake, both during that meal as well as the following meal. This is because soluble fiber expands when it mixes with water, creating the feeling of fullness. Moreover, many high-fiber foods like fruits and vegetables are high in volume and nutrients, but low in calories. Filling up your plate with these foods can increase the amount you eat without increasing the calories you consume.
A high-fiber diet is also linked to higher secretion of the hormone GLP-1. This is the hormone that weight-loss medications like Wegovy mimic because they can reduce hunger and help you lose weight. Eating soluble fiber naturally raises how much GLP-1 your body produces after you eat.
How to increase fiber intake
If you’re convinced that eating more fiber is a good idea, don’t try to raise your intake too fast, as this can lead to gastrointestinal discomfort like gas, bloating, diarrhea, and constipation. Instead, increase it more gradually to let your GI system get used to the extra fiber.
Good sources of fiber include fruits and vegetables, nuts and seeds, beans and legumes, and whole grains. Here are some simple ways to incorporate more of those fiber-rich foods into your diet:
- Add ground flaxseed to your smoothie.
- Sprinkle chia seeds on Greek yogurt or your overnight oats.
- Add beans or chickpeas to a salad.
- Cut up raw vegetables to dip in some hummus or tzatziki for a snack.
- Swap out white rice for quinoa, which is higher in fiber.
- Snack on berries, apples, or pears.
- Swap out juices for whole fruits and vegetables — and keep the skin on your apples!
- Swap out regular pasta for chickpea pasta.
- Choose a whole wheat bread with at least 3g of fiber per serving.
- Make your own trail mix with homemade popcorn, nuts, and dried fruit.
- Add a fiber supplement like psyllium husk to your morning routine.
The bottom line
Fiber can be either soluble, meaning it mixes with water and turns into a gel, or insoluble, meaning it does not mix with water and instead helps bulk up your stool. Eating enough fiber can help improve your heart health, reduce your blood sugar, keep your GI tract moving smoothly, and help manage your weight. Most people do not get the recommended amount of fiber — a number that varies based on your age and sex. If you want to boost your intake, do it gradually to avoid feeling gassy or bloated.
This content is for informational purposes only and does not constitute medical advice, diagnosis or treatment. It should not be regarded as a substitute for guidance from your healthcare provider.