…and that’s probably because they are. For acne, I strongly recommend the old “five a day” mantra because plant foods are loaded with healthy antioxidants and vitamins which are impossible to get from meat.
But there’s a catch, one that you may have experienced. Many acne patients are confused to find that when they eat these healthy foods, they get unexplained bursts of acne. They get acne just like if they eat a sugar-loaded cake or milk chocolate.
At first glance there’s no explanation. A slice of fresh watermelon contains just 5 grams of sugar, no gluten, no trans-fats and certainly no additives like vegetable oil. Acne patients everywhere are scratching their heads.
In the end, most write these reactions off as a simple food allergy. But the truth is that these reactions to seemingly clean foods are explained by a natural set of plant compounds that for some, may be just as dangerous as sugar.
These reactions are explained by FODMAPs, a group of natural carbohydrates found all across the plant kingdom.
In this article we will cover the following topics:
- What FODMAPs are.
- The types of FODMAPs and how they impact digestion.
- How FODMAPs cause acne.
- The causes of FODMAP sensitivity.
- How to establish whether you have a sensitivity.
- What you can do about it.
Let’s get started:
What are FODMAPs?
The term FODMAP stands for Fermentable Oligosaccharides, Discahherides, Monosaccharides, And Polyols. In short, they are a group of natural short chain carbohydrates which are poorly absorbed in the human digestive system and hence cause typical IBS-like symptoms such as pain, gas, and stomach upset.
In the world of official medicine, FODMAPs are increasingly recognised as a major cause of bowel diseases such as irritable bowel syndrome (IBS), especially over the last five years. The problems occur when FODMAPs fail to be absorbed by the gastro-intestinal tract and instead sit in your digestive system, where they meet pathogenic bacteria living in your intestine.
This bacteria ferments the FODMAPs which, ordinarily in humans, will only produce mild, barely noticeable, or even non-existent discomfort. But many people today have a FODMAP sensitivity, meaning that the fermentation produces excessive amounts of methane, carbon dioxide and by-products. Furthermore, in sensitive people these sugars have an osmotic effect; they increase fluid movement and suck in water.
The result is the IBS-like symptoms of bloating, gas and pain. The practical result is that many people cannot eat these seemingly nutritious plant foods without severe discomfort, and they’re left with no explanation as to why. FODMAPs can be found in a wide variety of foods, from onions to apples, to cabbage and red kidney beans.
People all over the world are wondering why healthy foods give them digestive problems and acne, and FODMAPs are the culprit.
FODMAP sensitivity may affect up to 35% of people according to one study on Australian people. What’s more, FODMAP sensitive people do not have a uniform sensitivity to all FODMAPS; one person might be unable to digest oligosaccharides, another might have problems from polyols.
Study after study is flooding out; over the last five years countless have concluded that a low FODMAP diet is effective for treating irritable bowel syndrome. For instance, one review published in 2010 found that avoiding dietary FODMAPs reduced the bloating, pain and discomfort from irritable bowel syndrome in 75% of patients. The scientists concluded that “the low FODMAP diet provides an effective approach to the management of patients with functional gut symptoms. The evidence base is now sufficiently strong to recommend its widespread application”.
Meanwhile, an Australian study from 2014 gathered 30 patients with IBS and 8 healthy volunteers and assigned them to either a normal or low FODMAP diet for 21 days. The subjects with IBS had significantly reduced symptoms while eating the FODMAP diet. That lead the scientists to conclude that “a diet low in FODMAPs effectively reduced functional gastrointestinal symptoms”.
Then there’s this study, which found that a low FODMAP diet reduced irritable bowel syndrome just as effectively as traditional dietary advice. 75 IBS patients taken from a clinic in Sweden were all randomly assigned to diets that were either low in FODMAPs or contained the standard dietary strategies given to IBS patients (regular meal patterns, less fat, avoidance of certain vegetables like onions and cabbage, smaller meals).
Both groups ate the diets for 4 weeks. Of the 67 patients who completed the study without getting ill, the FODMAP and traditional diets both significantly reduced IBS scores and were about equal in their reduction of bloating, gas, inflammation and pain.
That study was published just last year, in 2015. Furthermore, about five other studies were published last year too, including this review, and this review which found that a low FODMAP diet could reduce IBS in 37-45% of patients.
Make no mistake, FODMAPs are one of the most under-discussed dietary villains today.
Types of FODMAPs explained in detail
Firstly, we have the monosaccharides, which solely includes fructose. Fructose is a natural plant sugar found in fruits and vegetables in varying ratios to glucose and sucrose (which itself is 50:50 glucose and fructose). Fructose is criticised by paleo people all the time as being the worst sugar on earth and cited as a reason to minimise fruit intake, and it does indeed cause problems behind acne such as fatty liver in excess.
Normal intakes are healthy, but in FODMAP sensitive people, the gastrointestinal tract lacks an enzyme called GLUT-2, which aids the absorption of fructose from the intestine into the liver. Furthermore, foods like apples and pears have a dramatically higher amount of fructose to compare to glucose, and in humans the digestion of glucose is a big source of GLUT-2. Without GLUT-2, the fructose gets moved along for dangerous fermentation by bacteria.
Hence, FODMAP patients are sensitive to both fructose rich foods (honey, agave nectar, corn syrup) and plant foods with a sugar ratio skewed in favour of fructose (apples, watermelons, blackberries, mangoes, pears).
Next we have the disaccharides. Disaccharides, as a food group, have only one member: lactose. Lactose sensitivity is really an entirely different phenomenon to FODMAPs. Lactose sensitive people lack the bacterial family lactase, and hence the sugar (found in milk, yoghurt and other dairy) gets fermented by other bacteria. However, you’ll almost certainly know already if you are lactose intolerant and in this article we are concerned with the other, hidden FODMAPs.
Next on the list is the oligosaccharides. Here things get more complicated; these sugars are more structurally complex and many people have minor sensitivities to them. The main oligosaccharides are raffinose, galactans, and fructans. Raffinose is a trisaccharide (containing three sugar types) composed of fructose, galactose and glucose. This is a signature FODMAP of green vegetables as opposed to fruits; raffinose is found in beans, cabbage, brussel sprouts, broccoli, asparagus, whole grains, and other vegetables.
Unlike ruminants, humans, pigs, and other animals with one stomach (monogastric) lack the a-GAL enzyme required to break down raffinose and hence it passes undigested to intestinal bacteria, which do possess the a-GAL enzyme. By fermenting the raffinose the bacteria produces gases such as carbon dioxide, methane and hydrogen, thus causing some of the gas from FODMAPs. While most humans on earth can ferment low levels of raffinose without problems, some are sensitive even to tiny amounts.
Fructans are chains of fructose molecules. These are also found in vegetables, but especially root vegetables like garlic, onions, and agave root. They are also found in leeks, asparagus, artichokes, and wheat.
Again, humans lack the enzymes to digest fructans as they get fermented by bacteria. Common symptoms of fructan intolerance include abdominal pain. Then there’s galactans, a combination of raffinose and stachyose, which function very similarly. Galactans are a chief FODMAP in beans such as lentils, chickpeas and red kidney beans.
Finally, one of the FODMAP groups mainly found in fruit is the polyol. Polyols consist of natural sugar alcohols such as sorbitol, xylitol, mannitol, and maltitol. You might have heard of these sugar alcohols being added to cakes and chocolate as low-glycaemic sugar-substitutes. Well, they occur naturally as well, and are found in abundance in apples, apricots, avocados, cherries, peaches, pears, watermelons, cauliflower, green peppers, mushrooms and isolated retail versions of the sugar alcohols themselves.
The first is sorbitol, which is a natural sugar alcohol with a sweet taste. It is slowly digested and is known to cause abdominal pain, flatulence, and mild to severe diarrhea. Sorbitol has been directly linked to irritable bowel syndrome and other gastrointestinal disorders. Common sources of sorbitol are corn syrup, apples, pears, peaches, apricots, avocado, lychee and prunes.
Secondly we have mannitol, a sweet tasting crystalline alcohol. Mannitol is known to have a laxative effect, like many sugar alcohols. It is found in strawberries, onions, celery, mushrooms, pumpkins, snow peas, and cauliflower.
Thirdly, there’s maltitol, the signature FODMAP of grain-based foods like rye and wheat. The classic symptoms of maltitol include excessive flatulence and abdominal pain. Luckily, rye, wheat and barley are so unhealthy that all acne patients should avoid them anyway.
Finally, we have an extremely common natural sugar substantiate called xylitol. This sugar alcohol is found in the fibres of many fruits and vegetables, but especially berries, oats, mushrooms, and sugar canes. Xylitol seems to be a gentler FODMAP than the other polyols, though it has been linked to diarrhoea in high doses.
The key point that unites all FODMAPs is this: we either entirely lack the enzymes to digest them as a species, or those with a FODMAP sensitivity have an impaired ability to digest them.
The link to acne
If you don’t browse through natural health websites constantly then you have probably never even heard of FODMAPs. Until the last few years neither had most scientists. For the longest time, people all over the western world experiencing gas, pain and bloating blamed celiac disease or gluten intolerance for nearly all digestive woes…
…but now scientists are realising that FODMAPs are just a big a culprit, if not bigger for the average person. Paleo followers, who don’t even eat bread, cereal or grains in any form, are getting digestive problems and discovering the evils of FODMAPs.
For example, have you even wondered why an apple breaks you out? There’s no obvious explanation, but an apple is one of the most heavily concentrated sources of FODMAPs in the world. It contains polyols, fructose in a poor ratio to glucose, and oligosaccharides such as raffinose.
FODMAPs have not been shown directly in scientific studies to cause acne yet, but the link is strong.
For instance, IBS has been linked to skin conditions such as dermatitis. Allergic reactions to many foods trigger a blood increase in inflammatory chemicals such as histamine. Celiac disorder is similar to FODMAP sensitivity syndrome in many ways. Your gastrointestinal tract cannot properly process gluten and it gets both fermented and attacked by your immune system, resulting in damage to the intestinal wall and gut bacteria.
If your immune system learns that your digestive system cannot tolerate a food such as apples, eventually it may trigger an inflammatory response every time you eat it.
Excessive fermentation of FODMAPs might fuel the rise of pathogenic gut bacteria, which damage your intestinal permeability and lead to leaky gut syndrome. Too many bacterial strains can also crowd out the healthy ones and inhibit nutrient absorption, as well as the direct production of nutrients such as vitamin K2 from fermentation.
High intake of FODMAPs has been directly linked to causing an overgrowth of bad bacteria, rather than just being caused by it. This 2015 study found that by restricting fermentable short-chain carbohydrates in 27 patients with IBS, total gut colonies of bacteria fell. However, levels of beneficial bacterial strains such as Clostridium and Akkermansia muciniphila were substantially increased, whereas a pathogenic bacteria called Ruminococcus torques was substantially decreased.
While FODMAPS are not proven to cause acne, judging by the evidence I believe that they almost certainly do. The simple explanation is that FODMAPs have a massive effect on your gut health, and your gut health has a massive effect on acne.
Throughout my research on acne I always wondered why so many people reacted to foods like watermelon or blackberries which should be fantastic for acne given their antioxidants and vitamins. We now have the answer. The case of FODMAPs fits the mystery like glove.
What causes a FODMAP sensitivity?
As for the causes of FODMAP sensitivity, which are all-important because as acne patients, we want to remove the sensitivity entirely so that we can benefit from lots of different nutritious and healthy foods, chronic stress is one of the most important ones.
Stress is a well-known disruptor of the GLUT-2 enzyme, the transporter responsible for the uptake of fructose and galactose in the gastrointestinal tract. If you don’t absorb the molecules then they make their way to the patiently waiting bacteria and get fermented.
Stress also has a massive effect on the composition of human gut flora, increasing unhealthy strains and decreasing beneficial ones like lactobacilli and bifidobacterium. Furthermore, stress reduces the variety of your gut bacteria.
Scientist have not fully discovered how stress impacts gut bacteria so strongly. However, the butterflies in your stomach, a sinking feeling, or the feeling that your stomach no longer exists you get from strong emotions are all signs of the effect stress has on your digestion.
Another major factor is gut bacteria that is crippled in the first place. In the Western world, our way of life is extremely sanitised compared to Africa or poor parts of Asia. Of course that’s a great thing because it means we don’t routinely die from infectious, dirty water, or infected wounds.
However, there’s a major downside, in that we are not exposed to varied bacterial strains from dirt, from unclean plant matter, or from live bacteria in our surroundings.
The result is that citizens of third world countries have dramatically more varied gut bacteria than westerners do. That’s linked to FODMAPs because if you lack healthy gut bacterial strains, you can’t prevent the bad strains from taking over, and they are the ones that cause digestive problems when fed FODMAPs.
Any previous dietary choice that causes an overgrowth of bad bacteria may lead to FODMAP sensitivity. These include a high sugar diet, which feed candida and other yeasts, excessive oral antibiotic usage, which wipes out friendly bacteria, and too many chemicals in foods which do the same.
The condition known as SIBO, small intestinal bacterial overgrowth, also causes FODMAP sensitivity by interfering with the digestion of sorbitol, fructose, and other short-chain carbohydrates. In fact, SIBO is strongly linked to FODMAPs in studies and acne patients are ten times more likely to have SIBO according to one study.
Genetics may also be a cause of FODMAP sensitivity. For example, some of us might have a naturally poorer ability to manufacture GLUT-2 and digest fructose, or we may be predisposed to bad bacteria taking over.
Polyol FODMAPs like xylitol and sorbitol are partially absorbed; what if some humans can absorb them more efficiently while others fail completely? FODMAP sensitivity has only turned into a big scientific topic in the last five years, so the answers should roll in very soon.
Is FODMAP sensitivity causing your acne?
If for example, you have already eliminated the classic acne supervillains like sugar, wheat, trans-fats, vegetable oils (not healthy at all; discussed in my eBook), yet are still getting acne outbreaks like clockwork, FODMAPs could be the culprit.
FODMAPs aren’t a niche issue either, the study above found that 35% of Australians have a sensitivity. Sensitivities exist all over the world, including Asian countries like China, Thailand, and Vietnam.
The signs and symptoms of a FODMAP sensitivity can be literally any digestive problems, including bloating, cramps, gas, pain, and discomfort when eating high FODMAP foods. Here’s a brief guide to the FODMAP status of many foods:
Fruits high in FODMAPs – apples, apricots, blackberries, cherries, dried fruits (way too much fructose), grapes, mango, nectarines, pears, peaches, persimmon, plum, watermelon.
Fruits medium in FODMAPs – unripe banana, longon, rambutan, lychee, grapes.
Fruits low in FODMAPs – ripe banana, blueberry, cantaloupe melon, grapefruit, strawberry, raspberry, honeydew melon, kiwi fruit, lemon, lime, mandarin, orange, papaya, pineapple, rhubarb, passion fruit.
Vegetables medium in FODMAPs – avocado, beetroot, broccoli, brussel sprouts, butternut pumpkin, cauliflower, celery, fennel bulb, green peas, mushroom, sauerkraut, guacamole.
Vegetables low in FODMAPs – alfalfa, bamboo shoots, bean sprouts, bell peppers, bok choy, carrots, cherry tomatoes, chives, cucumber, eggplant, endive, ginger root, green beans, kale, lettuce, tomato, swiss chard, spring onions, zucchini, spinach, seaweed (nori), parsnips, pickles, olives.
Almost all the foods listed are healthy and nutritious aside from the high sugar content of fruits like bananas, which won’t cause acne from one isolated consumption anyway. If any of those foods trigger acne on your face without being a full-blown, throat swelling, hospital visit allergy, then a FODMAP sensitivity is highly likely.
If you currently eat a standard diet and suffer from digestive issues, they could be caused by any ingredient. You could have a gluten intolerance (which are distributed more widely than the 1% who are full-blown celiacs), or you could be allergic to the protein compounds in milk, or lactose.
The real killer sign is if your diet is completely clean. FODMAPs are a big reason why followers of the paleo diet, who completely eliminate gluten by removing all grains like wheat, rye and barley, often get digestive problems six months down the line.
Many paleo followers are middle aged people who grew tired of a lifetime of following the traditional dietary advice only to watch their health and vitality wither away. Then they jumped aboard the paleo train and began guzzling down more nutritious plant foods per month than they’d probably eaten during their entire life before. But their gut bacteria was so starved of prebiotics for years that it couldn’t cope with all the plant molecules such as FODMAPs now flooding in.
If that scenario fits you like a glove then FODMAPs may be the menace behind all of your problems.
If you’re chronically stressed out, you might be sensitive. If you have been diagnosed with IBS, the disease might be caused by FODMAPs. If you have been diagnosed with small intestinal bacterial overgrowth (SIBO), a FODMAP sensitivity is extremely likely.
If you want scientific confirmation, then good news: FODMAPs have become such a recognised medical issue that doctors now offer a breath test.
However that creates a big dilemma for us: many high FODMAP plant foods are otherwise terrific for acne. Garlic has potent anti-inflammatory powers, apple skins are like an armour of antioxidants, and cabbage has vitamin C and so forth. A FODMAP sensitivity writes off a vast swathe of acne-friendly foods.
Hence, the best approach is to cure your FODMAP sensitivity using the following information. Firstly, you should eliminate all FODMAPs for approximately two months. As well as relieving your acne and digestive system from immediate discomfort, this will allow pathogenic strains of gut bacteria to fall and healthy ones to increase.
You should closely monitor your symptoms to prove once and for all whether you do have a sensitivity; monitor your acne outbreaks and your digestion. Also keep your sugar intake low to starve unhealthy microorganisms of fuel.
In the first week, to be completely sure, you could eliminate all FODMAPs for two days and then bring them back. If acne comes roaring back like magic then you’ll know you have a sensitivity.
Both during and after the two months, you should take steps to enrich your gut flora in other ways so that once you reintroduce FODMAP-rich foods, your stomach will be more able to digest them.
If you’re not sensitive to dairy proteins or lactose, then yoghurt, kefir, or blue cheeses are full of beneficial bacteria. Depending on how bad your FODMAP sensitivity is, you can buy sauerkraut juice off the internet; cabbage is full of FODMAPs, but the bacteria consumes many of the short-chain carbohydrates during the fermentation process. The same applies to other fermented vegetables. Fermented soy such as natto and tempeh are also full of good bacteria. You need to cram in as much bacterial boosting strength as you can without setting off the FODMAP alarm.
Hence you should continue to eat a wide variety of low-FODMAP plant foods, as they contain prebiotics which help existing bacteria to grow. Dark chocolate, for instance, contains flavonoids which healthy lactobacilli strains love to feast on. Nuts like pistachios boost gut bacteria superbly. Many plant foods contain natural prebiotics unrelated to FODMAPs, so eat whatever you can get your hands on.
Once two months are up and you’re implemented all that, you can gradually reintroduce some moderate-FODMAP foods like broccoli, beetroot, etc. Broccoli is a simple one to test your sensitivity on. If you notice that after this protocol, you mysteriously no longer get acne from moderate FODMAP foods, then you can drive forwards; keep experimenting with more FODMAP foods from the list above to see what your acne can now withstand
If FODMAP sensitivity does have a genetic component then you will be partially limited forever but if it is mainly caused by our modern lifestyle, it may well be curable if you keep playing around with the strategies above.
The acne threat from FODMAPs is very real and FODMAPs should take their place alongside sugar as a plant compound that many acne patients should watch out for.
FODMAPs are not fundamentally unhealthy because it is a faulty digestive system that brings out the dangers in them. Nevertheless, if you’re sensitive you can improve your acne significantly by eliminating them, and then by fixing the sensitivity at its root.
What you should definitely not do is adopt a low-FODMAP diet if you’re not sensitive, simply because it sounds like a cool extra strategy. Too many FODMAP-rich foods are nutritious and high in antioxidants to justify avoiding them if it’s anything but totally necessary.
Thanks for reading!