Foods that make your farts smell more and more, I finally found them all! There is one category you would never expect...

Farts are big things, but if you fart in the wrong place, it can become a big deal, such as on a first date, at a work meeting... Do you know what is in a fart? Why are there sometimes more farts but not smelly, and sometimes more farts and smelly? This has a lot to do with the food you eat. In this article, we will tell you which foods you should eat in moderation if you want to fart less and have less smelly farts.

The main source of farts: gas produced by intestinal fermentation of food

First, let's talk about where farts come from. Eating too fast or chewing gum and swallowing a lot of gas is a source of farts, but it is only a negligible source because it is mostly excreted from the body through burping. The indigestible and unabsorbed ingredients in food are transported to the large intestine and fermented by bacteria in the large intestine to produce gases, which are the main force of farts. These gases mainly include nitrogen, carbon dioxide, hydrogen, and methane. Although they are large in quantity (accounting for >99%), they have no smell, so they are responsible for most farts; farts also contain a small amount of hydrogen sulfide, methyl mercaptan, and dimethyl sulfide (accounting for <1%). Hydrogen sulfide has a pungent smell of rotten eggs, which makes them the stinkiest farts.

Image source: Pixabay

If you collect all the farts you pass every day, the average volume is 600-700 ml. These farts are mainly released after meals, and the average number of farts is 14-18 times a day. In fact, it is normal to fart up to 25 times a day, but if you feel that you fart a lot and/or your farts are smelly, then you should control the amount of these foods that are easy to produce gas or odor.

8 Foods That Can Cause Gas

1

beans

Every 100 grams of dry soybeans contains about 2.5 to 5 grams of soy oligosaccharides, mainly stachyose and raffinose. There is no enzyme in the small intestine to digest them, and they cannot be absorbed if they cannot be digested into monosaccharides, so they can only be transported to the large intestine. In the colon part of the large intestine, they are fermented by bacteria such as lactobacillus and bifidobacterium, producing a large amount of carbon dioxide and hydrogen. This is why eating beans causes a lot of farts. In addition to soybeans, various beans such as mung beans and adzuki beans also contain soy oligosaccharides. Although they have more starch content and can be eaten as staple foods, don't use them to completely replace staple foods, otherwise it will be too embarrassing to fart endlessly.

Image source: Pixabay

If they eat too much, they will not only fart a lot, but also smell bad. This is because all kinds of beans are rich in protein. Among the amino acids that make up protein, methionine and cysteine ​​are sulfur-containing amino acids. If there are too many, they cannot be absorbed and enter the large intestine to be fermented into hydrogen sulfide, so the smell comes. So how much should we eat? The Chinese Residents' Dietary Guidelines recommend that 15 to 25 grams of soybeans should be eaten every day. 25 grams of soybeans is the amount of a small handful for women, which is about 365 grams when converted into soy milk. If you add miscellaneous beans and whole grains together, it is recommended to eat 50 to 150 grams a day. This amount only accounts for 1/4 to 1/3 of the whole day's grains. If it is distributed to miscellaneous beans alone, the proportion will be even lower, so don't use them to completely replace staple foods.

In addition to controlling the amount you eat, there are 3 other ways to help you fart less when eating beans.

(1) Soaking beans before cooking or eating tofu skin, tofu, or tofu shreds. This is because soy oligosaccharides are water-soluble. Soaking beans for a long time by changing the water several times before cooking can reduce the amount of soy oligosaccharides. In addition, soy products such as tofu skin, tofu, and tofu shreds will also greatly reduce the content of soy oligosaccharides because they have undergone a water squeezing process.

(2) Eating bean sprouts can also destroy oligosaccharides. Studies have shown that most soybean oligosaccharides can be used up within 1 to 4 days of germination. This shows that eating bean sprouts is also a good choice for reducing constipation.

(3) Eat edamame. Edamame is the young part of soybeans. Its oligosaccharide content is lower than that of mature soybeans. It is another better choice for you to fart less.

2

milk

Not all people fart a lot after drinking milk. Only people who are lactose intolerant will do so. This is because these people lack the enzyme to break down lactose. Lactose can only be absorbed into the blood after being digested into monosaccharides. If lactose that enters the blood cannot be absorbed, it will enter the large intestine and be fermented by bacteria to produce gas. In addition to gas, lactose intolerance is often accompanied by abdominal pain and diarrhea. If you suspect that you are lactose intolerant, go to the hospital for a check-up. However, the good news is that even if you are lactose intolerant, you don’t have to avoid milk. This is because symptoms will only appear if you drink more than 240 ml of milk a day, which is about one box. Even if you are more sensitive, it doesn’t matter. Just drink 0 lactose milk. The lactose in it has been broken down into two monosaccharides, galactose and glucose. You can also drink yogurt and eat cheese. After the fermentation process, most of the lactose is fermented into lactic acid.

3

High fructose fruits

Who will fart a lot after eating high-fructose fruits? Those who have fructose malabsorption (FM) are those who cannot fully absorb the fructose they eat for unknown reasons (science has not yet thoroughly studied it). The fructose that cannot be absorbed will enter the large intestine and be fermented by bacteria into hydrogen, carbon dioxide and methane, causing more farts. The seven fruits, lychee, banana, pear, apple, kiwi, mango and fig, have relatively high fructose content; the three vegetables, asparagus, broccoli and sweet peas, also have high fructose content; honey and beverages with added fructose syrup and high fructose corn are also rich in fructose; in addition, fructose will also be produced after the decomposition of sucrose, and the white sugar, brown sugar and rock sugar commonly added to sweets and sweet drinks are mainly composed of sucrose. Therefore, if people with fructose malabsorption want to produce less gas, most sweets, sweet drinks and fruits with high fructose content should be restricted.

4

Prunes and prune juice

Prunes are one of the few fruits rich in sorbitol. Its products, dried prunes and prune juice, contain sorbitol at 14.7 g/100 g and 6.1 g/100 g, respectively. Like the oligosaccharides mentioned above, sorbitol cannot be absorbed by the human body and will be fermented and produce gas in the large intestine. Studies have shown that daily intake of as little as 5 grams may cause flatulence and farting, which means that drinking only 100 ml of prune juice may cause many people to fart frequently. In addition to the natural food prunes rich in sorbitol, some sugar-free foods also use sorbitol, as well as xylitol, mannitol, and isomalt as sugar substitutes (sweeteners), so if you eat too much of these foods, you will also fart a lot.

5

Garlic, onion, leek, asparagus

These four vegetables are rich in oligofructose, which is an ingredient that cannot be digested and absorbed. Once it enters the large intestine, it can be fermented by bacteria to produce gas, causing you to fart. In addition, vegetables like garlic, onions, and leeks also contain organic sulfides, and eating too much of them can cause you to fart smellily.

Image source: Pixabay

6

Cruciferous vegetables

Cruciferous vegetables, like beans, are rich in raffinose, which can cause people to fart. In addition, they also contain organic sulfides, which can produce hydrogen sulfide through intestinal bacterial fermentation, so they are also a group of foods that make people fart a lot and have smelly farts. Common cruciferous vegetables are: broccoli, cauliflower, kale, kale, cabbage, Chinese cabbage, pakchoy, radish, and mustard. Which one do you eat that is most likely to cause farts? There is a general term for the gas-producing ingredients rich in the above 6 types of food, that is, FODMAP (Fermentable Oligosaccharides, Disaccharides, Monosaccharides And Polyols), which translates to fermentable oligosaccharides, disaccharides, monosaccharides and polyols. Above, I have only listed some very typical high-FODMAP foods. In addition, I have compiled and summarized more high-FODMAP foods based on the latest literature. You can come and see which food is more likely to cause farts after eating.

7

Animal protein

As mentioned earlier, eating too much beans will cause you to fart. In fact, eating too much animal protein such as meat, eggs and milk will also cause you to fart. This is because the amino acids that make up animal protein, such as methionine, cysteine, and taurine, all contain sulfur. If you like to eat big fish and meat, or eat multiple eggs a day, or drink milk as water, it is easy to consume too much protein. The undigested or unabsorbed part will enter the large intestine and be fermented by bacteria into hydrogen sulfide, which will then cause you to fart easily. So how much of these foods should be eaten is reasonable? The Chinese Residents' Dietary Guidelines recommend that an average adult eat 1 egg, 300-500 grams of milk, and 70-150 grams of meat per day. This meat includes livestock meat, poultry meat, and aquatic products. It is especially recommended that you eat less red meat (lean meat of pigs, cattle, and sheep). This is because studies have found that the amount of hydrogen sulfide in feces is significantly correlated with eating more red meat.

8

Foods that carry gas

This is easy to understand. Drinks such as soda water, carbonated drinks, and beer contain carbon dioxide gas. If you drink too much, you will not only burp, but you will also easily cough.

Image source: Pixabay

These are the 8 major categories of food that make you fart easily or produce smelly farts. However, smelly farts cannot be entirely blamed on food. Some foods will not cause smelly farts for some people, but may cause extremely smelly farts for others. This may be related to intestinal bacteria. In addition, when constipation or irritable bowel syndrome occurs, farts tend to be smellier. So if your farts are always smelly no matter what you eat, it is best to check if there is something wrong with your intestines.

References

[1] https://health.clevelandclinic.org/why-do-farts-smell

[2]Kurbel S, Kurbel B, Vcev A. Intestinal gases and flatulence: Possible causes of occurrence. Medical Hypotheses. 2006;67:235–239. doi: 10.1016/j.mehy.2006.01.057.

[3]Hasler WL. Gas and Bloating. Gastroenterol Hepatol (NY). 2006 Sep;2(9):654-662. PMID: 28316536; PMCID: PMC5350578.

[4] Messina, Mark J .Legumes and soybeans: overview of their nutritional profiles and health effects[J].The American Journal of Clinical Nutrition, 1999.DOI:10.1093/ajcn/70.3.439s.

[5] Suarez FL, Springfield J, Furne JK, et al.Gas production in humans ingesting a soybean flour derived from beans naturally low in oligosaccharides[J]. The American Journal of Clinical Nutrition, 1999.DOI:10.1093/ajcn/69.1.135.

[6] East, Jerry W., TOM Nakayama, and SB Parkman. "Changes in Stachyose, Raffinose, Sucrose, and Monosaccharides During Germination of Soybean1." Crop Science 12.1(1972):7-9.

[7] Espinosa-Martos I, Rupérez P. Soybean oligosaccharides. Potential as new ingredients in functional food. Nutr Hosp. 2006 Jan-Feb;21(1):92-6. PMID: 16562819.

[8] Suarez FL, Savaiano DA, Levitt MD. A comparison of symptoms after the consumption of milk or lactose-hydrolyzed milk by people with self-reported severe lactose intolerance. N Engl J Med. 1995;333:1–4.

[9]Benardout M, Le Gresley A, ElShaer A, Wren SP. Fructose malabsorption: causes, diagnosis and treatment. Br J Nutr. 2022 Feb 28;127(4):481-489. doi: 10.1017/S0007114521001215. Epub 2021 Apr 5. PMID: 33818329.

[10]Mehta M, Beg M. Fructose Intolerance: Cause or Cure of Chronic Functional Constipation. Glob Pediatr Health. 2018 Mar 8;5:2333794X18761460. doi: 10.1177/2333794X18761460. PMID: 29552600; PMCID: PMC5846912.

[11] USDA Food Database

[12] https://www.va.gov/files/2023-10/FODMAP%20Diet%20Reintroduction%20Phase.pdf

[13]Stacewicz-Sapuntzakis M, Bowen PE, Hussain EA, Damayanti-Wood BI, Farnsworth NR. Chemical composition and potential health effects of prunes: a functional food? Crit Rev Food Sci Nutr. 2001 May;41(4):251-86. doi: 10.1080/20014091091814. PMID: 11401245.

[14]Bauditz J, Norman K, Biering H, Lochs H, Pirlich M. Severe weight loss caused by chewing gum. BMJ. 2008;336(7635):96–7.

[15] https://www.sciencedirect.com/science/article/pii/S1756464622004376#b0555

[16]https://www.health.harvard.edu/a_to_z/gas-flatulence-a-to-z

[17] CJ Richardson, EAM Magee, JHCummings

A new method for the determination of sulphide in gastrointestinal contents and whole blood by microdistillation and ion chromatography

Clinica Chimica Acta, 293 (1–2)(2000), pp. 115-125, 10.1016/S0009-8981(99)00245-4

This article is a work of Science Popularization China-Starry Sky Project

Produced by: Science Popularization Department of China Association for Science and Technology

Producer｜China Science and Technology Press Co., Ltd., Beijing Zhongke Xinghe Culture Media Co., Ltd.

Author: Gu Chuanling, Deputy Secretary General of Capital Health Nutrition and Gastronomy Association, Registered Nutritionist

Review | Ruan Guangfeng, Deputy Director of Kexin Food and Health Information Exchange Center