Food combining is a way of eating that respects our physiological chemistry and in particular the chemistry of digestion: its basis stands upon the understanding that certain combinations of food are digested way better and efficiently than other types of food combinations.

Although, the human body is not designed to eat wrong combinations of food, it does not mean it cannot do it: our body is without any doubt our best alley and will do its best at all times to digest and assimilate any type of food and food combinations alike; The harder for the body it is to break down the food and assimilate its nutrients, the greater the expenditure of energy overall, as well as a greater amount of digestive by-products produced such as mycotoxins, and undigested residues.

The body's resilience to an incorrect food combination lifestyle is accentuated as we age due to a general reduction of enzymes in the body, so we may start to feel lack of energy after eating (afternoon slump), bloating, gassiness, malabsorption, diarrhoea, and digestive troubles in general more often that during our youth.

I just mentioned enzymes, right?. And I find very important to explain clearly what are enzymes and what they do in the body, so that you have a much better understanding of this topic.

On the physical level, all our life processes depend on the functioning of enzymes which are living proteins that regulate all basic biochemical and metabolic processes. It is estimated there are 75.000 to 100.000 different enzyme systems in the body, and there is strong evidence that enzyme preservation is linked with longevity and vitality. 

- Enzyme regulate all body processes.

- Enzymes are important for digestion and assimilation of nutrients.

- Enzymes are essential for detoxification from internal pollution and external ecological pollution.

- Enzymes help repair DNA and RNA, and maintain optimal immune function.

- Enzymes transform and store energy in the body.

- Enzymes make active hormones, and participate in their own productive cycle.

- Enzymes dissolve fibre and prevent clotting.

- Enzymes have anti-inflammatory and analgesic effects, and they prevent edema.

In regards to digestion, enzymes are needed for all digestive processes, and are produced by the body and supplied from dietary sources: Enzymes are secreted by the salivary glands in the mouth, by the cells lining the stomach (gastric enzymes), by pancreatic exocrine cells, and in the small and large intestinal tract.

Each food group has its own ideal digestive "cocktail"; some combination of digestive chemistry work out well and other don't. Let’s have a look together at each food category, analysing how to eat it in a more stomach-friendly way.


Proteins require an acid medium to be broken down into their simplest amino acid form: Acid secretions for protein digestions are secreted in the stomach and the main ones are Hydrochloric Acid and the enzyme called Pepsinogen, which become Pepsin once activated by the stomach acid. Another important secretion for protein digestion is Gastrin, an endocrine hormone secreted by the stomach after exposure to protein that enters the bloodstream and ultimately returns to the stomach and stimulate the production of more HCL and intrinsic factor (key component for B12 absorption). I like to keep this category of food within the food combining discussion rather simple. And so I include into this category only concentrated and high-quality protein sources (animal protein); the only plant protein that I include in this group is soy protein.

The essential rule of food combining regarding protein is that this category shouldn't be mixed with concentrated starch/carbohydrate food. Keep reading to know why.


The digestion of starchy food begins and is aided by proper chewing; amylase is the enzyme responsible for digesting starch and is produced by the salivary glands in the mouth. Amylase breaks down complex carbohydrates into smaller chains, or even simple sugars.

Amylase is the enzyme required for digestion of carbohydrates and it is an alkaline enzyme, whereas HCL and pepsinogen are acidic enzymes and are required for the digestion of proteins. When you eat protein food with a starchy food, your body will first produce Amylase while chewing the food, and then when you swallow it, the body will produce HCL and pepsinogen, that will then neutralise the Amylase, because when an acid substance meet an alkaline substance, they neutralise each other. Now your stomach has a pool of chemical compounds that are not ideal for digesting either protein or carbohydrates. These will lead without a shadow of a doubt to a greater energy expenditure and there are chances you feel tired and bloated for example. A classic scenario of this combination is potatoes with chicken, or pasta with cheese.

Now, I really want to emphasise that you don't need to eat like this at all times: you can do if you want, but it's not necessary. As a matter of fact the more you do it, the better your digestion and energy levels will be. But we all want to enjoy great food and great dishes at restaurants or with friends at theirs, so don't put pressure on yourself and don't feel restricted. Start slowly when you are eating at home and then increase according to your health conditions and goals; also once you start eating this way, you really understand how simple it is and that it is not a restricting way of eating at all.


Sugars are quickly absorbed into the blood stream, which is a good thing, because if they stay in the stomach, they soon cause fermentation. Fruit is high in sugar and it is in this category.

Many health experts would recommend eating fruit with a protein in order to slow-down the sugar-release into the bloodstream and I respect this advice of course because it makes sense and it does slow the release of sugars. But this suggestion needs to be a bit more individualised according to who you are talking to: if you are talking with people that have candida for example, or they have poor digestion, low stomach acid, slow metabolism etc. than they should really consume fruit alone. And that’s what I do, and I think generally speaking is the best way to eat fruit… with an empty stomach.

When sugars are combined with carbohydrates, the sugar inhibit the production of Amylase, thus slowing down digestion of starches, and also has an inhibiting effect on the secretion of gastric enzymes. The sugar can't leave the stomach until the starchy food does, so it stays there, leading to fermentation, gassiness and excess acidity.

When combined with protein, the length of time involved in digesting protein becomes a serious issue. Again, the sugars sit in the stomach with the digesting proteins, leading to fermentation, and as the sugar has an inhibiting effect on the secretion of gastric enzymes, the chemistry of digestion is not able to work fully on the proteins, causing them to take even longer to be digested.


Fats are slow to digest requiring acids and a range of enzymes, and some chemistry that the fat itself provide, such as lecithin, a phospholipid. Phospholipids are in higher quantities in unsaturated fats, making these fats easier to digest than saturated fats. As fat are slow to digest, they slow the digestion of anything eaten with them, but an exception is eating fats with chlorophyll-rich vegetables as these foods counteract the tendency of fats to slow digestion.


High-water content raw fruits and leafy greens digest well even when you drink water during your meal; Many fruit and green juices are improved when diluted with pure water. Fruit juices should be drunk alone, not with meals and vegetable juices should also not be drunk while eating, but can be enjoyed twenty minutes before a meal. Green juices (without any fruit) in the other hand digest well if eaten with a raw salad.

The digestion of complex proteins and complex carbohydrates, which requires significant amount of digestive juices and time to digest, is negatively impacted when digestive juices are diluted by liquids.

Key Guidelines of food combining:

Below I list basic guidelines that will assure you to eat according the Food Combining rules, without going to too extreme making it more difficult to follow through.

The two main and essential rules of food combining are:

1.  Eat fruit on an empty stomach.

2.  Don’t mix concentrated, high-quality protein with very starchy foods at the same meal.

… other healthful guidelines are:

- Drink water before a meal, not with the meal

- Consider leafy greens and vegetables neutral; they mix well with either complex proteins, complex carbohydrates, nuts, seeds, and legumes.

- Ideally, don't eat more than one complex protein at a time. Although, if you like, you can eat two complex carbohydrate foods together 

- Vegetarian protein food sources such as seeds, nuts, legumes, and beans should be eaten with salads and vegetables, but can also be mixed with complex carbohydrates, although bear in mind this is a slightly heavy combination, which equals more energy consuming

-Consider oils as neutral: use them in moderation and do not cook with them.

Start applying Food combining rules five days a week, or one meal a day and notice how you feel after; it isn't a restricted way of eating, rather it is an intelligent way to keep your digestion healthy, your energy levels productive, and your body fit without dieting. 

Bon appétit !