I recently went for a meal with a group of friends, most of whom were omnivores, and of course pretty quickly the conversation turned to diet (bound to happen when you all have plates of food arriving!). At one point the topic rose its head about food combining, the question was asked should we eat fruit with a meal or not.
The question was asked in general but all eyes turned to me as the one in the group who was vegan and therefore ate lots of fruit and had actually studied the topic. So what was my answer? it depends on the fruit and the meal!
What actually frustrated me that evening was I couldn’t remember all the specifics that I had learnt, even more so that this was a topic I had, had to write a 5000 word essay on, albeit 8 years ago.
So when I got home I thought I would go through my notes and try to summarise my essay for you in about 1000 words that may help you make an informed choice about how you combine foods. Not just about vegan food combining, but food combination in general.
What is food combining?
So the first thing is what is food combining? Well food combining in essence is based on the fact that fruits, proteins and starches all have different digestion rates, and that combining these foods incorrectly can cause a range of symptoms, not least indigestion, flatulence, bloating, weight gain and ill health.
So why is that? well to explain we need to have at least a basic understanding of the human digestive process. Let’s start with a simple fact, protein and carbohydrate are digested differently.
The digestion process – Carbs
The digestion of carbohydrates start in the mouth, with the digestive enzyme amylase which is present in saliva. Interestingly this digestive activity can begin with just the smell or site of food with the brain sending signals to the salivary to start secretion.
This enzyme starts to break down the carbohydrate once the food has entered the mouth and we start to chew. Once swallowed the food will pass down through the oesophagus and in to the acid environment that is our stomach, at this point the amylase stops working.
It is only when these carbohydrates leave the acid environment of the stomach that the process for digestion can be continued and this is because it returns to the more alkaline environment of the small intestine where more amylase enzymes are secreted by the pancreas.
The digestion process – Proteins
Protein however is very different, digestion is not started in the mouth because it requires an acid environment to start the digestion process. Thus the stomach is where it needs to be in order for us to digest it but depending on the complexity of the protein it could take up to 3 hours until it is broken down in to the smaller amino acids which are known as peptides.
This is able to happen because the stomach contains hydrochloric acid which is needed to active the enzyme pepsin which is required to digest protein. Once these peptides leave the stomach they will be further broken down by the enzyme peptidase which is also secreted by the pancreas, this will ensure that they are broken down in to the individual amino acids that the body can absorb.
We evolved like this
Ok so are we saying that proteins and carbohydrates shouldn’t be mixed? that seems rather simplistic and also impossible to achieve bearing in mind most food contains levels of both. That is of course correct so in practical terms what it means is avoiding combining foods that have highly concentrated levels of protein with those that have a highly concentrated level of starch.
When we think about this and look back to our evolution over hundreds of thousands of years this makes sense. The general scientific consensus is that we have evolved eating primarily a vegan/vegetarian based diet with the occasion meal of meat or fish depending on what part of the world we were.
However, these would have been eaten typically as a meal on their own and not combined. Do we really think that our Paleolithic ancestors had the resources available to create the “balance meal” myth that we are sold today. In fact the paleo diet we are sold today is a complete myth and unfortunately is just another marketing ploy to sell a diet solution, a great talk by archaeological scientist Christina Warriner debunks this here with her Ted talk.
What about fruits?
So we have ascertained that we should avoiding combining foods that have highly concentrated levels of protein with those that have a highly concentrated level of starch but what about fruits? Well of course at certain times of year and depending on where in the world we would have had access to fruits.
Fruit on the whole is a great fuel for quick energy and their simple carbohydrates require less digestion. Again fruit would have been eaten on its own. Most fruit ferment quickly once they are ripe and typically take less than 30 minutes to pass through the stomach, imagine then what happens to your digestive system if you eat a stake and follow it with melon for desert!
There are some exceptions within the fruit family which are fruits that do not readily ferment like bananas and apples. So how should fruit be eaten? well the fast fermenting fruit should be eaten on its own at least 30 minutes prior to a meal and no less than 2 hours post. The non-fermenting fruits could be mixed with other complex carbohydrate rich foods such as oats, so a fresh banana with the oats in your acai bowl are fine.
And foods that have both carbs and protein?
Ok so we have covered fruit and briefly discussed protein and carbohydrates but what about those foods that combine protein and carbs?
Well as mentioned the consensus is that for the majority of the time our ancestors would have eaten a varied vegan diet consisting of both root and leaf vegetables, seeds, nuts pulses and legumes, yes, a mixture of foods that contain both protein and carbohydrate but not a protein dense as meat.
The combination of these foods typically should not cause a problem for our digestive system.
What about refined and heavily cooked food?
Although this article is about food combining I think it worthwhile just touching on the effect refined and heavily cooked food can have on the body and its digestion process. We know that the more processed, refined or cooked food is the less nutritious it is.
This of course leads us to the conclusion that raw and lightly cooked whole foods should be eaten instead of highly processed, overcooked foods. In terms of our evolution the introduction of refined high sugar foods are a brand new invention, one of which the body is not naturally adapted to deal with.
The flood of fast releasing sugars that many of these foods give us not only dramatically increase blood sugar levels but can also feed some of the unwanted micro-organisms that can thrive in our gut.
Food combining – a summary for optimum digestion
So to simplify all the above we can in essence break down food in to five basic groups for combining.
Starches, including potatoes, rice, wheat, oats, pasta, bread etc combine well with vegetables and with non fast-fermenting fruit.
Vegetables, including all salad and root vegetables (excluding potato), lentils chickpeas etc combine well with starches, non fast fermenting fruit and high protein food
Non fast fermenting fruit, including apples, bananas, coconut etc combine well with starches and vegetables
High protein foods, including meat, fish, poultry, cheese, egg etc combine well with vegetables
Fast fermenting fruit, including mangoes, melon, papaya, most berries, pears, peaches etc should always be eaten on their own.
And vegan food combing?
Vegans only have one simple rule that they should follow which is to eat fast fermenting fruits separately. Vegan food combing – easy isn’t it!