When it comes to getting lean, a lot of websites will tell you it’s protein and fat that count. The low carb/ketogenic diet trend continues, and with it the idea that carbohydrates are stalling your fat loss. And it is true that a diet high in sugars and highly processed carbohydrates (like white bread) is doing no one any favours. However, avoiding all carbohydrates also means you are missing out on essential fibre.
Fibre is the part of plant foods that cannot be digested so passes through. It provides no energy but removes toxins and wastes from the digestive system. Because of this, plenty of fibre is essential for good gut health and prevents certain cancers.
More importantly, fibre also feeds the good bacteria in the gut. There has been an explosion in studies over the past 10 years showing just how important healthy gut bacteria are. Having diverse and healthy gut bacteria has been linked to all kinds of health benefits, including improving gut health (such as reducing symptoms of IBS); lowing cholesterol and the risk of heart disease; reducing the risk of developing diabetes; and improving mood1. However, of particular interest to us, people with a healthy microbiome tend to be a lower weight2. In fact, studies have shown that normal weight people have higher fibre intakes than obese people3.
Another reason why a higher fibre intake helps with fat loss is it allows you to eat more food. Fibre is bulky, making you feel fuller for longer. Your stomach responds to the volume of food eaten, not mass. In other words, you feel full when your stomach is stretched by bulky foods. What’s more, the stretch signal is one of the first to reach the brain and tell you to stop eating. Fibrous foods fill you up faster and help prevent overeating. Unfortunately, a common theme of high fat, high sugar foods is they pack a lot of calories into a very small space. In nutrition circles, we call these foods calorie dense. For example, 100g of raw spinach is a LOT of salad, but it has less than 30 kcal. On the other hand, most people would have no problem eating 100g of milk chocolate, all 500 kcal of it. Of course, your body will realise you’ve just downed a load of calories eventually. But it can take more than 20 minutes, during which time you’re still hungry!
The NHS currently recommends getting at least 30g of fibre a day. Sadly, in my experience, most people are getting less than 20g a day. The best sources are plant foods like fruits, vegetables, beans, lentils, nuts, seeds and whole grains. This is why ketogenic diets, where you avoid most carbohydrates, are usually very low in fibre.
What’s more, these foods tend to be high in vitamins and minerals. They are nutrient dense, but lower in calories. For example, my favourite breakfast of porridge with frozen berries and ground flaxseeds absolutely fills a large bowl once the liquid has been absorbed. Yet it only has 200 kcal. On the other hand, there are several brands of cereal or granola where a standard 40g serving barely fills a third of the bowl and can be 250 kcal, before you add the milk!
Choosing plant based, high fibre foods feeds the good bacteria in your gut and means you can eat “a lot” of food and still keep the calorie count down. A double win for fat loss!
For delicious high fibre recipes, including a Farm Bean Stew with 15g of fibre per portion, click here! And if you enjoyed this post, don’t forget to like, share and subscribe!
1. Slavin J. Fiber and prebiotics: mechanisms and health benefits. Nutrients. 2013 Apr 22;5(4):1417-35. doi: 10.3390/nu5041417.
2. Menni C, Jackson MA, Pallister T, Steves CJ, Spector TD, Valdes AM. Gut microbiome diversity and high-fibre intake are related to lower long-term weight gain. Int J Obes (Lond). 2017 Jul;41(7):1099-1105. doi: 10.1038/ijo.2017.66. Epub 2017 Mar 13.
3. Davis JN, Hodges VA, Gillham MB. Normal-weight adults consume more fiber and fruit than their age- and height-matched overweight/obese counterparts. J Am Diet Assoc. 2006 Jun;106(6):833-40.