Soluble Fiber And Carbs: Friend Or Foe On Keto?

The keto diet is a high-fat, moderate-protein, and very low-carb eating plan. The diet is generally made up of 70 to 75 percent fat, 20 to 25 percent protein, and 5 to 10 percent carbohydrates. While the keto diet is a popular way to lose weight, it can also cause constipation and headaches. It is important to note that fiber is not counted as a carb on the keto diet because it is not digested by the body. Soluble fiber, found in fruits and vegetables, is especially high in keto-friendly foods like Brussels sprouts and asparagus. This type of fiber can ease constipation and boost good bacteria in the gut.

Soluble fibre doesn't raise blood glucose

Soluble fibre is a form of water-soluble carbohydrate that can't be digested by the body. Instead, it dissolves in water, forming a gel-like substance in the stomach that slows down digestion. This has a positive impact on blood glucose levels, as it gives digestive hormones more time to act and prevents the small intestine from absorbing carbohydrates too quickly.

Research has found that even modest increases in soluble fibre intake can help to lower blood glucose levels. A study published in the New England Journal of Medicine in 2000 compared a moderate fibre diet (24g of total fibre including 8g of soluble fibre) with a high fibre diet (50g of total fibre including 25g of soluble fibre) over 6 weeks. The high fibre diet saw a reduction in pre-meal blood glucose levels by 0.7 mmol/l compared to the moderate fibre diet, as well as reducing triglyceride levels and post-meal blood glucose levels.

Soluble fibre is particularly present in fruits and berries, especially apples, strawberries and blueberries; beans, pulses and lentils; and foods such as oats, peas, black beans, lima beans, Brussels sprouts, and avocados.

The Academy of Nutrition and Dietetics recommends that adult women should consume 25 grams of fibre per day, with 10 to 15 grams coming from soluble fibre. For adult men, the recommended amount is 38 grams, with the same proportion of soluble fibre.

Soluble fibre is found in all fruits and vegetables

Soluble fibre is a type of dietary fibre that is essential to gut and overall health. It is a carbohydrate that the body cannot digest. Instead, it helps to bulk up stools and can be used as a food source for good bacteria in the large intestine. Soluble fibre also draws water into the gut, softening stools and supporting regular bowel movements. This type of fibre can help you feel fuller for longer and may also lower cholesterol and blood sugar levels.

Soluble fibre is not counted as a carb on a low-carb diet because it does not raise blood glucose. However, it does provide 2 calories for every gram, not as glucose, but as a by-product of fermentation in the colon (short-chain fatty acids).

The recommended daily amount of fibre for adult women is 25 grams, and for adult men, it is 38 grams. For optimal health, 10 to 15 grams of this should come from soluble fibre. Unfortunately, most people do not meet these recommended intakes, with the average American consuming only 17 grams of fibre per day.

To increase your soluble fibre intake, it is best to start slowly and build up gradually. It is also important to drink plenty of water, as this helps soluble fibre form a gel, which aids digestion and prevents constipation.

Insoluble fibre is also known as roughage

Insoluble fibre, also known as roughage, is a type of dietary fibre that does not dissolve in water. Instead, it absorbs water and sticks to other materials to form stools. Insoluble fibre is inert to digestive enzymes in the upper gastrointestinal tract and is only partially or fully fermented in the colon.

Insoluble fibre is found in plant-based foods such as legumes, whole grains, cereals, vegetables, fruits, nuts, and seeds. It is present in both the soluble and insoluble form in varying amounts, depending on the plant. For example, the skin of many fruits and vegetables is typically high in insoluble fibre, while the inside is usually higher in soluble fibre.

Insoluble fibre has several important functions in the body. Firstly, it improves bowel health and prevents and treats constipation by forming softer, bulkier, and more regular stools. This leads to better colorectal health and a reduced risk of colorectal conditions such as hemorrhoids and diverticulitis.

Additionally, insoluble fibre plays a role in regulating blood sugar levels and reducing the risk of diabetes. Some research suggests that it may also help support insulin sensitivity.

To increase your intake of insoluble fibre, it is recommended to consume more vegetables, such as cauliflower, green beans, potatoes, and carrots. Whole-grain cereals and oatmeal are also good sources, as well as whole-wheat flour, which can be used in baking and cooking.

Insoluble fibre does not dissolve in water

Soluble fibre is a type of fibre that dissolves in water, helping to form a gel-like substance in the intestines. It is often recognised for relieving diarrhoea. Soluble fibre is hydrophilic, meaning it attracts water, and in doing so, it removes excess fluid, which is how it helps decrease diarrhoea. It can also help lower LDL "bad" cholesterol and blood glucose levels, reducing the risk of diabetes.

Insoluble fibre, on the other hand, does not dissolve in water. It passes through the intestines undigested and includes plant cellulose, hemicellulose, and lignin. Insoluble fibre plays a significant role in relieving constipation and regulating digestion. While it doesn't dissolve in water, it attracts water into the stool, making it softer and easier to pass with less strain on the bowel. This could help promote bowel health and regularity. Insoluble fibre may also help support insulin sensitivity and reduce the risk of diabetes.

Insoluble fibre is found in foods such as wheat bran, vegetables, and whole grains. It adds bulk to the stool and helps food pass more quickly through the stomach and intestines. Examples of foods containing insoluble fibre include flax seeds, chia seeds, whole grains, bran, brown rice, cereals, and rolled oats.

Both soluble and insoluble fibres are important for a healthy diet and support many body systems, including digestive health and the prevention of certain types of cancer.

Fibre is essential for good intestinal function

Fibre promotes regularity and prevents constipation. It slows down digestion and stabilises blood sugar levels. Fibre also acts as fuel for your gut microbiome, the large collection of bacteria, viruses, fungi, and other microbes that live in your gastrointestinal tract. These microbes exist symbiotically with your digestive system and support energy harvesting, digestion, and immune defence.

There are two main types of fibre: soluble and insoluble. Soluble fibre dissolves in water and can be metabolised by the "good" bacteria in the gut. Insoluble fibre does not dissolve in water but attracts water to the intestine, adding bulk to stools and promoting the movement of waste through your digestive system. This type of fibre is beneficial for people struggling with constipation and irregularity.

Good sources of soluble fibre include flax seeds, chia seeds, blackberries, broccoli, cauliflower, avocado, spinach, coconut, and wheat bran. Insoluble fibre sources include vegetables such as cauliflower, carrots, green beans, and potatoes.

It's important to increase your fibre intake gradually and to drink plenty of water to prevent constipation.

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