Milk intake raises circulating IGF-1, and higher IGF-1 increases prostate cancer risk; this is the mechanism behind the dairy-prostate cancer link ('the same hormone that makes a calf grow').

Original statement

مراجعة Cancer Causes & Control عام 2017 وثّقت أن شرب الحليب يرفع مستوى عامل النمو IGF-1 في الدم، وأن ارتفاع IGF-1 يزيد خطر سرطان البروستاتا — وهو نفس الهرمون الذي يجعل العجل ينمو بسرعة.

not verbatim – paraphrase. Translation by the project; the Arabic wording is authoritative.

Translation

Milk intake raises circulating IGF-1, and higher IGF-1 increases prostate cancer risk; this is the mechanism behind the dairy-prostate cancer link ('the same hormone that makes a calf grow').

Origin

Source status

Archive editors

Attribution

Archive editors (eltayebat.com, rule 'dairy')

Origin

https://eltayebat.com/rule/dairy/

Attribution uncertainty

Editorial narrative and study selection by the archive operators, not shown to be Elawady's own words; the archive homepage says the forbidden section is documented 'independently of Dr. Diaa's words'.

Claimed mechanism

Dairy protein/milk increases endogenous IGF-1; IGF-1 promotes prostate cell growth.

Claimed health effect

Prostate cancer.

Population concerned

Men.

Geographic restriction by Elawady

none found

Scientific assessment

Potentially true – Some evidence points in favour of the statement, but it is not sufficient for a clear judgement.

Certainty of evidence: low – Further research is likely to change the assessment considerably.

1. What was claimed?

Milk raises IGF-1 and IGF-1 raises prostate cancer risk.

2. What is demonstrably correct?

A-DRY-14: moderate evidence that IGF-I rises with milk intake (about 0.10 SD per 1 SD of milk) and that prostate cancer risk rises with IGF-I (OR 1.09 per SD, 1.03-1.16; prospective studies 1.07, 1.02-1.12). I-DRY-06 (IPD, 17 prospective studies): OR 1.29 (1.16-1.43) top vs bottom fifth of IGF-I. The mechanism is biologically plausible.

3. What is wrong or exaggerated?

The effect of milk on IGF-1 is small (about 0.10 SD), was read from albatross plots rather than pooled, and the largest rises came from very small short-term trials in children. IGF-I was not associated with advanced prostate cancer (OR 1.04, 0.94-1.14), the authors state that the evidence that IGF-I increases prostate cancer risk 'is not strong', and they did not test whether IGF-I mediates a dairy-prostate link (A-DRY-14). Calling it 'the mechanism' therefore overstates the evidence. The calf comparison is rhetorical: the IGF-1 increase is mainly the body's own production in response to protein, not 'calf hormone' absorbed from milk (A-DRY-14 discusses circulating levels, not absorption). Other protein sources can also raise IGF-1 (not quantified here). The mechanism also applies to cheese (concentrated milk protein), which the system allows.

4. What remains unclear?

Whether IGF-1 mediates any dairy-prostate association; magnitude of cancer risk attributable to dairy-induced IGF-1; relevance for aggressive disease.

5. Which studies support it?

A-DRY-14, I-DRY-06.

6. Which studies contradict it?

None directly against the two links; limiting: A-DRY-14 itself (no association of IGF-I with advanced prostate cancer; mediation untested).

7. What applies to Germany and Europe?

Not a basis for official recommendations to avoid dairy.

8. What is known about Egypt?

No data.

9. What practical conclusion is appropriate?

A plausible, modest mechanism; it supports moderation of very high dairy-protein intakes rather than elimination of specific dairy types.

Assessment details

Rationale for certainty of evidence

Each link has some support: the archive's own review rates the evidence as moderate that milk raises IGF-I and that IGF-I is associated with prostate cancer (A-DRY-14), and pooled prospective data show OR 1.29 for the top vs bottom fifth of IGF-I (I-DRY-06). But the milk effect on IGF-I (0.10 SD per SD of milk) is a visual estimate, not a pooled result, and comes largely from small short-term trials in children; IGF-I was not associated with advanced prostate cancer; the authors call the IGF-I-prostate cancer evidence 'not strong'; and mediation of a dairy-prostate link by IGF-I was not tested. A mechanism cannot be more certain than the dairy-prostate association it is meant to explain (C-DRY-04: potentially true, low certainty).

Source quality

Archive editorial; figures correctly reported from A-DRY-14.

Regional transferability

Biological; transferable.

Individual exceptions

Children need growth factors; IGF-1 increase with dairy in children is part of normal growth physiology.

Regional scope of the claim

general (biological/medical)

Last reviewed

25 October 2026 provisional

In plain language

Drinking more milk slightly raises the level of a growth hormone called IGF-1 in the blood, and men with higher IGF-1 levels are somewhat more likely to get prostate cancer. The archive's own review rates the evidence for both links as moderate, but says the second link is 'not strong' and found no link with advanced prostate cancer. It has not been shown that IGF-1 is what connects dairy with prostate cancer. Cheese, which the system allows, is rich in the same milk protein.

Studies on this claim

Regional context

Germany / EU

Not a basis for official recommendations to avoid dairy.

Egypt

No data.

• Antimicrobial use in food animals and antibiotic growth promoters
• Hormones in poultry, meat, milk and farmed fish
• Dioxins, PCBs and PFAS in eggs and other animal foods
• Aflatoxin M1 in milk and dairy products
• Import controls and the meaning of RASFF notifications for Egyptian products

What applies in my country?

General scientific assessment

Potentially true Milk modestly raises IGF-1 and IGF-1 is weakly linked to prostate cancer; this is a plausible but unproven mechanism, not proof of harm.

The following areas of food safety are relevant to this statement:

• Veterinary medicines and antibiotics
• Hormonal growth promoters
• Contaminants (heavy metals, PFAS, PCBs, dioxins, nitrate)
• Mycotoxins (mould toxins)
• Controls, imports, recalls, labelling

Dairy

Limits: legal rules describe what is allowed, not what every single food contains. Measurement data come from samples and are meaningful only together with their method details.

Country of residence or purchase Compare with another country

References

1. Does milk intake promote prostate cancer initiation or progression via effects on insulin-like growth factors (IGFs)? A systematic review and meta-analysis.. Harrison S et al.. Cancer Causes Control 2017 · PMID 28361446 · DOI 10.1007/s10552-017-0883-1
2. A Meta-analysis of Individual Participant Data Reveals an Association between Circulating Levels of IGF-I and Prostate Cancer Risk.. Travis RC et al.. Cancer Res 2016 · PMID 26921328 · DOI 10.1158/0008-5472.CAN-15-1551