Lactose intolerance is “an impaired ability to digest lactose, a sugar found in milk and other dairy products,” according to the National Institutes of Health (NIH).
Lactose intolerance in infants is caused by a mutation in the LCT gene, which results in a life-long intolerance. This condition is inherited, rare, and most common in Finland.
In adults, lactose intolerance is caused by normally decreasing activity of the LCT gene, which means adults may experience increasing inability to digest lactose as they age. About 65% of the adult human population has this sort of lactose intolerance, which results in abdominal pain and other gastrointestinal consequences after eating dairy products.
According to the NIH, in adults lactose intolerance shows up most often in people of East Asian heritage, affecting 70 to 100% of the population. Encyclopaedia Britannica adds that the condition affects about 75 to 90% of Native Americans, Black people, Asians, Mediterraneans, and Jewish people. Only about 5% of Northern and Central Europeans have lactose intolerance.
Percent of Country’s Population with Lactose Intolerance
| Country | Prevalence |
|---|---|
| Afghanistan | 82% |
| Algeria | 62% |
| Angola | 94% |
| Armenia | 98% |
| Australia | 44% |
| Austria | 22% |
| Azerbaijan | 96% |
| Belgium | 15% |
| Botswana | 88% |
| Brazil | 60% |
| Cambodia | 68% |
| Cameroon | 89% |
| Canada | 59% |
| Chile | 56% |
| China | 85% |
| Colombia | 80% |
| Cyprus | 16% |
| Czech Republic | 81% |
| Democratic Republic of the Congo | 95% |
| Denmark | 4% |
| Egypt | 68% |
| Estonia | 28% |
| Ethiopia | 77% |
| Finland | 19% |
| France | 36% |
| Gabon | 93% |
| Germany | 16% |
| Ghana | 100% |
| Greece | 55% |
| Hungary | 39% |
| India | 61% |
| Iran | 88% |
| Iraq | 93% |
| Ireland | 4% |
| Israel | 89% |
| Italy | 72% |
| Japan | 73% |
| Jordan | 56% |
| Kazakhstan | 75% |
| Kenya | 39% |
| Kuwait | 56% |
| Lebanon | 78% |
| Malawi | 100% |
| Malaysia | 87% |
| Mexico | 48% |
| Mongolia | 88% |
| Morocco | 73% |
| Mozambique | 95% |
| Myanmar | 92% |
| Namibia | 93% |
| Netherlands | 12% |
| New Zealand | 10% |
| Niger | 13% |
| Nigeria | 87% |
| Norway | 12% |
| Oman | 96% |
| Pakistan | 58% |
| Papua New Guinea | 91% |
| Poland | 43% |
| Portugal | 40% |
| Republic of Congo | 93% |
| Russia | 61% |
| Rwanda | 49% |
| Saudi Arabia | 28% |
| Senegal | 79% |
| Solomon Islands | 99% |
| Somalia | 94% |
| South Africa | 81% |
| South Korea | 100% |
| Spain | 29% |
| Sri Lanka | 73% |
| Sudan | 55% |
| Sweden | 7% |
| Syria | 95% |
| Taiwan | 88% |
| Tanzania | 45% |
| Thailand | 84% |
| Tunisia | 84% |
| Turkey | 69% |
| Uganda | 87% |
| Ukraine | 61% |
| United Kingdom | 8% |
| United States | 36% |
| Uruguay | 65% |
| Uzbekistan | 92% |
| Vietnam | 98% |
| Western Sahara | 53% |
| Yemen | 100% |
| Zambia | 98% |
Sources
Kelli Glaser, “Lactose Intolerance,” britannica.com (accessed Mar. 25, 2020)
National Institutes of Health US National Library of Medicine, “Lactose Intolerance” ghr.nlm.nih.gov, Mar. 17, 2020
Christian Løvold Storhaug, Svein Kjetil Fosse, and Lars T Fadnes, “Country, Regional, and Global Estimates for Lactose Malabsorption in Adults: A Systematic Review and Meta-Analysis,” thelancet.com, Oct. 1, 2017
