Research

What research says about lactose tolerance

Findings describe groups of people. They are not a personal limit and they cannot predict how you will feel.

• EFSA concluded that one lactose threshold for all people with lactose intolerance cannot be determined. Some people report symptoms after less than 6 g, while most people with lactose maldigestion tolerate up to 12 g as a single dose with no or minor symptoms.

  Sources: EFSA Panel on Dietetic Products, EFSA Journal 2010;8(9):1777

• Many adults with lactose malabsorption or intolerance tolerate about 12 g of lactose in a single intake with no or mild symptoms.

  Sources: National Institute of Diabetes and Digestive and Kidney Diseases, Last reviewed February 2018; Institute for Quality and Efficiency in Health Care, Updated 20 November 2024; Misselwitz B, Gut 2019;68:2080-2091

• A systematic review found moderate-quality evidence that most adults with presumed lactose intolerance or malabsorption tolerate 12 to 15 g of lactose.

  Sources: Shaukat A, Annals of Internal Medicine 2010;152(12):797-803

• Larger amounts, about 15 to 18 g, appear to be tolerated when dairy is eaten together with other foods.

  Sources: Deng Y, Nutrients 2015;7(9):8020-8035; Misselwitz B, Gut 2019;68:2080-2091; Institute for Quality and Efficiency in Health Care, Updated 20 November 2024

• Spreading lactose over the day matters: up to about 24 g across a day is often tolerated.

  Sources: Institute for Quality and Efficiency in Health Care, Updated 20 November 2024; Misselwitz B, Gut 2019;68:2080-2091

• Symptoms depend on dose, food context, residual lactase and other digestive conditions, so responses vary between people. People with irritable bowel syndrome may be more sensitive.

  Sources: Deng Y, Nutrients 2015;7(9):8020-8035; Misselwitz B, Gut 2019;68:2080-2091

• Lactose malabsorption (not fully absorbing lactose) is not the same as lactose intolerance (having symptoms). Many people with malabsorption have no symptoms after a standard serving.

  Sources: Misselwitz B, Gut 2019;68:2080-2091; Shaukat A, Annals of Internal Medicine 2010;152(12):797-803

Sources

• Scientific Opinion on lactose thresholds in lactose intolerance and galactosaemia

  EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA), European Food Safety Authority. EFSA Journal 2010;8(9):1777.

  What it supports: A single lactose threshold for all people with lactose intolerance cannot be determined. Symptoms have been described after less than 6 g in some people, while most people with lactose maldigestion tolerate up to 12 g as a single dose with no or minor symptoms.

  Limits: A 2010 food-safety opinion about labelling thresholds, not guidance for an individual. EFSA has not assessed or endorsed LactoGo.

• Eating, Diet, & Nutrition for Lactose Intolerance

  National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH. Last reviewed February 2018.

  What it supports: Many people could have about 12 g of lactose, roughly the amount in 1 cup of milk, with few or no symptoms. Adding dairy gradually and with meals may help.

  Limits: Patient-information page, not a trial. Last reviewed in 2018.

• What can lactose-intolerant people eat?

  Institute for Quality and Efficiency in Health Care (IQWiG, Germany), InformedHealth.org. Updated 20 November 2024.

  What it supports: Up to about 12 g of lactose at once (around 250 ml of milk) and up to about 24 g across a day are often tolerated. Combining lactose-containing foods with other foods slows digestion.

  Limits: General health information. (The NCBI Bookshelf copy NBK534631 could not be opened for verification, so this InformedHealth.org page is cited.)

• Systematic review: effective management strategies for lactose intolerance

  Shaukat A, Levitt MD, Taylor BC, MacDonald R, Shamliyan TA, Kane RL, Wilt TJ. Annals of Internal Medicine 2010;152(12):797-803.

  What it supports: Moderate-quality evidence that most adults with presumed lactose intolerance or malabsorption tolerate 12 to 15 g of lactose.

  Limits: Most included trials enrolled people with lactose malabsorption rather than symptomatic intolerance. Trials differed too much to pool. Searched to November 2009.

• Update on lactose malabsorption and intolerance: pathogenesis, diagnosis and clinical management

  Misselwitz B, Butter M, Verbeke K, Fox MR. Gut 2019;68:2080-2091.

  What it supports: Many people with lactose malabsorption tolerate at least 12 g (about 250 ml of milk) without problems, and larger doses may be tolerated with food or spread over the day. Whether symptoms occur depends on several factors.

  Limits: Expert review. This is the 2019 update, not the 2013 paper in United European Gastroenterology Journal, which could not be opened.

• Lactose intolerance in adults: biological mechanism and dietary management

  Deng Y, Misselwitz B, Dai N, Fox M. Nutrients 2015;7(9):8020-8035.

  What it supports: Doses of 15 to 18 g appear to be tolerated when dairy is taken with other nutrients. The tolerance threshold depends on the dose and on residual lactase. People with irritable bowel syndrome may react to lower doses.

  Limits: Narrative review. Figures differ within the paper (it also cites up to 20 g), which shows how uncertain any single number is.

Citing a source does not mean the source's authors or organisation have reviewed, validated or endorsed LactoGo.

How estimates are calculated

• Estimates are calculated by fixed rules from food-composition data, never generated by AI. An AI model does not supply any lactose number.
• Preferred data, best first: verified product data, food-composition databases, peer-reviewed research or reference tables, then labelled category estimates.
• Lactose = grams of food in your portion × lactose per 100 g. For one typical serving, the serving size in the reference table is used.
• A range is shown only where the data source publishes a range. LactoGo does not invent ranges.
• Lactose is never inferred from total sugar, and it is never read from a photo.
• A scan is not treated as eating. A food is counted only after you record or confirm that you ate it.
• If no reliable figure exists for a food, LactoGo says so. It is left out of totals and charts, and it is never counted as zero.
• Time periods with nothing recorded are shown as empty, not as zero.
• The dashboard ranges 0–12 g, over 12–24 g and over 24 g are illustrative tracking categories chosen by LactoGo. They echo population figures in the sources above (about 12 g in one intake, about 24 g across a day) but are not thresholds taken from EFSA or any other source, and they do not predict symptoms.
• The dashed 12 g line on the Day chart is a population research figure for a single intake. It is shown for context and is not a personal limit.

Limitations

• Table values are typical values. The lactose in your actual meal can differ with brand, recipe and portion.
• Your recorded experiences are self-reported and can be shaped by many things besides lactose, such as other foods, stress, medicines and other digestive conditions. They cannot show cause or predict future symptoms.
• LactoGo cannot diagnose lactose intolerance or establish a medically validated tolerance limit.
• Severe, persistent or worsening symptoms, or symptoms after small amounts, can have other causes. A doctor or pharmacist can help.