Bacon and pork: small trials, and the nitrite question left open

No strong trial sits behind this page. What exists is a handful of small randomised studies, and the most informative one is about giving the meat up. Twenty metabolically healthy men ate 240 g a day of red and processed meat for 14 days and mycoprotein for another 14, and in the mycoprotein period total cholesterol fell 6.74 percent and LDL cholesterol 12.3 percent from baseline. Those were secondary endpoints in twenty healthy men, measured as change from baseline inside one arm, and their cardiovascular risk scores barely shifted because there was little to improve. Pork on its own does less than its reputation. Forty eight community living older adults with a mean age of 78 were given pork meals four times a week for 12 weeks, or matched chicken meals. Cognition, grip strength, sit to stand, get up and go and the six minute walk came out the same, in a trial randomised by retirement village that ended with 19 people analysed in the pork arm and 12 in the chicken arm. The premise being tested was that the thiamin in pork would help. The NIH Office of Dietary Supplements does call pork a major source of thiamin in the US diet, and it also says heating reduces the thiamin in food and that a significant amount is lost when cooking water is thrown out. It gives no figure for pork itself, and its cooking-loss examples are bread and milk.

How much is actually in it

• The NIH Office of Dietary Supplements names pork a major source of thiamin in the US diet, and states that heating reduces thiamin content and that a significant amount is lost when cooking water is thrown out. — United States population, agency fact sheet for health professionals Evidence E source
  Pork named a major dietary thiamin source, thiamin reduced by heating and lost into discarded cooking water

What your body absorbs

• In 12 men on a controlled diet supplying 170 g of pork per 10 MJ, apparent selenium absorption was 94 percent, yet plasma selenium and glutathione peroxidase activity did not change across three 3 week periods. — 12 male volunteers aged 21 to 30, randomised crossover, strictly controlled diet, three periods of 3 weeks (n = 12) Evidence B source
  Apparent selenium absorption 94 percent plus or minus 2, retention 61 plus or minus 24 micrograms a day, no change in plasma selenium or glutathione peroxidase activity
• After leg resistance exercise, muscle protein synthesis rates did not differ between pork, egg, salmon, lentils and mycoprotein in 65 resistance-trained young adults. — 65 resistance-trained young adults, randomised parallel groups of 10 to 11 per food, tracer infusion and muscle biopsies to 300 minutes after exercise (n = 65) Evidence B source
  Myofibrillar synthesis rose after exercise and food with no differences between groups, and the per-group figures the abstract reports run from egg 161.0 plus or minus 6.1 to salmon 195.4 plus or minus 7.1 micromoles per kg per minute, with pork at 166.8 plus or minus 7.2

What it does to your health

• In 20 metabolically healthy men eating 240 g a day of red and processed meat for 14 days, switching to mycoprotein cut total cholesterol by 6.74 percent and LDL cholesterol by 12.3 percent from baseline. — 20 metabolically healthy male adults, investigator-blind randomised crossover, 14 days on each diet (n = 20) Evidence B source
  Total cholesterol -6.74 percent, P = 0.02, LDL cholesterol -12.3 percent, P = 0.02, waist circumference -0.95 cm against meat, P = 0.04

Safety, limits and interactions

• Pooling 12 cohort and 30 case-control studies, high bacon intake went with 37 percent higher gastric cancer risk (RR 1.37, 95 percent CI 1.17 to 1.61). For red meat the association held only in case-control studies and vanished in cohorts (RR 1.02, 95 percent CI 0.90 to 1.17). — participants of 12 cohort and 30 case-control studies of meat intake and gastric cancer, searched to April 2013 (n = 42 studies) Evidence C source
  Bacon RR 1.37, 95 percent CI 1.17 to 1.61, ham 1.44, sausage 1.33, processed meat overall 1.45, red meat 1.63 in case-control studies but 1.02, 95 percent CI 0.90 to 1.17, in cohorts
• In 358 raw pork products from Shandong markets and slaughterhouses, hepatitis E virus RNA was found in 1.8 percent of livers and 1.0 percent of pork meat, and the swine strains matched local human cases at over 92 percent nucleotide identity. — 358 raw pork products (166 livers, 96 kidneys, 96 pork meat), 388 pig farm faecal samples and 110 human HEV case sera, Shandong Province, April 2023 to March 2025 (n = 358 pork products) Evidence C source
  HEV RNA in 1.8 percent of livers, 1.0 percent of pork meat, 6.5 percent of pig faeces, none in kidney, and swine sequences sharing over 92 percent identity with local human HEV-4d

What people believe that the data does not support

• A meta-analysis of nine observational studies put cured meat and adult glioma at RR 1.48 (95 percent CI 1.20 to 1.83), with bacon at 1.31 and hot dogs at a non-significant 0.90. Its own authors concluded the data do not clearly support a causal link. — adults in nine observational studies of cured meat intake and glioma (n = 9 studies) Evidence C source
  Cured meat of all types RR 1.48, 95 percent CI 1.20 to 1.83, bacon 1.31, 95 percent CI 1.00 to 1.71, ham 1.64, hot dogs 0.90, 95 percent CI 0.63 to 1.25
• Across 28 studies in the Balkans, pooled hepatitis E seroprevalence was 5.68 percent (95 percent CI 3.48 to 9.12), and national pork consumption was not independently associated with it once assay type and publication year were accounted for. — adults in the general population and blood donors across 28 eligible Balkan studies (n = 28 studies) Evidence C source
  Pooled anti-HEV seroprevalence 5.68 percent, 95 percent CI 3.48 to 9.12, country estimates from 1.01 percent in Greece to 26.66 percent in Bulgaria, pork consumption not an independent moderator

Who this works differently for

• Giving community-living older adults four pork meals a week for 12 weeks produced no improvement in cognition, strength or physical function against matched meals made with chicken. The pilot trial enrolled 48 people and analysed 19 in the pork arm and 12 in the chicken arm. — 48 community-living older adults, mean age 78.2 years, retirement villages randomised to pork or chicken meals four times a week for 12 weeks (n = 48 enrolled, 19 pork and 12 chicken analysed) Evidence B source
  No difference between pork and chicken groups in cognitive tests, hand grip strength, sit-to-stand, get-up-and-go or six-minute walk

The bottom line

Bacon has a cancer number of its own, and it is not the one people quote. Pooling 12 cohort and 30 case-control studies, high bacon intake went with 37 percent higher gastric cancer risk (RR 1.37, 95 percent CI 1.17 to 1.61), from observational studies pooled together rather than from trials. In the same analysis red meat carried a raised risk only in the case-control studies, where diet was recalled after diagnosis, and the association disappeared in the cohorts (RR 1.02, 95 percent CI 0.90 to 1.17). The bacon estimate was never broken out by study design, so it may carry the same weakness. The brain tumour claim is thinner than its circulation suggests. A meta-analysis of nine observational studies put cured meat and adult glioma at RR 1.48 (95 percent CI 1.20 to 1.83), with bacon at 1.31 (95 percent CI 1.00 to 1.71) and hot dogs at a non-significant 0.90. Its own authors then showed that most of the included studies never adjusted for total energy intake, which can manufacture a positive association, and they concluded that the data do not clearly support a causal link. Who should be careful: anyone eating raw or lightly cooked pork, and pig liver more than pork meat. In 358 raw pork products from markets and slaughterhouses in Shandong, hepatitis E virus RNA was found in 1.8 percent of livers and 1.0 percent of pork meat, and RT-PCR finds viral RNA rather than virus shown to be able to infect anyone. No kidney sample was positive. The swine strains clustered with local human cases at over 92 percent nucleotide identity, this is one Chinese province, and cooking was not tested in that survey. Population level numbers do not carry the fear either. Across 28 Balkan studies, pooled hepatitis E seroprevalence was 5.68 percent (95 percent CI 3.48 to 9.12), ranging from 1.01 percent in Greece to 26.66 percent in Bulgaria, with substantial heterogeneity. National pork consumption was not independently associated with seropositivity once assay type and year of publication were accounted for, and those authors call that comparison exploratory. Seroprevalence is past exposure rather than current infection. Absorption has a twist worth carrying. In 12 men aged 21 to 30 on a strictly controlled diet supplying 170 g of pork per 10 MJ, apparent selenium absorption was 94 percent, and plasma selenium and glutathione peroxidase activity did not change across three periods of 3 weeks. Absorbing a mineral well is not the same as moving the proteins that use it. As a protein source pork is ordinary. In 65 resistance trained young adults given matched protein doses after leg exercise, muscle protein synthesis over the following five hours did not differ between pork, egg, salmon, lentils and mycoprotein, with 10 to 11 people per food. A five hour measurement is not muscle built over weeks. Two things this page cannot tell you. The EFSA assessment of nitrosamines in food is the agency position a bacon page most needs, and we could not retrieve it, so nothing here speaks to nitrite and that silence is a gap rather than reassurance. We also have no USDA composition record for this pair, which leaves the table above empty and the salt in bacon unstated on this page, so nothing here says what a rasher costs in salt.

Sources

1. bcpk-r2-09 · fact sheet
   The most common sources of thiamin in the U.S. diet are cereals and bread [8]. Pork is another major source of the vitamin. Dairy products and most fruits contain little thiamin [3]. ... Heating foods containing thiamin can reduce their thiamin content. ... Because thiamin dissolves in water, a significant amount of the vitamin is lost when cooking water is thrown out [3].
   NIH Office of Dietary Supplements, Thiamin fact sheet for health professionals · checked 2026-09-24
2. bcpk-r2-04 · randomised controlled trial
   Twelve male volunteers (age 21-30 years) participated in a randomised crossover study with strictly controlled diet containing 170 g pig meat/10 MJ per day and 106 +/- 13 microg Se/d for 3 x 3 weeks. ... The apparent absorption of Se was 94 +/- 2% (100 +/- 13 microg/d). ... Absorption and retention of Se from pig meat were high suggesting a high availability. However, the availability of pig meat Se for blood Se protein appears to be low.
   J Trace Elem Med Biol, 2004 · checked 2026-09-24
3. bcpk-r2-06 · randomised controlled trial
   MyoPS rates increased after exercise/food ingestion with no (temporal) differences between groups despite divergent plasma amino acid responses ... egg, 161.0 ± 6.1; pork, 166.8 ± 7.2; salmon, 195.4 ± 7.1; lentils, 175.8 ± 8.1; mycoprotein, 189.7 ± 8.4 μmol/kg/min (P < 0.0001, all)]
   Am J Clin Nutr, 2026 · checked 2026-09-24
4. bcpk-r2-03 · randomised controlled trial
   We leveraged samples from Mycomeat, an investigator-blind randomised crossover controlled trial in metabolically healthy male adults (n = 20), randomised to consume 240 g/day of red and processed meat for 14 days followed by mycoprotein, or vice versa. ... Mycoprotein consumption led to a 6.74% reduction in total cholesterol (P = 0.02) and 12.3% reduction in LDL cholesterol (P = 0.02) from baseline values.
   Eur J Nutr, 2023 · checked 2026-09-24
5. bcpk-r2-01 · meta-analysis of observational studies
   Twelve cohort and thirty case-control studies were included in the meta-analysis. Significant associations were found between both red (RR: 1.45, 95% CI: 1.22-1.73) and processed (RR: 1.45, 95% CI: 1.26-1.65) meat intake and gastric cancer risk generally. Positive findings were also existed in the items of beef (RR: 1.28, 95% CI: 1.04-1.57), bacon (RR: 1.37, 95% CI: 1.17-1.61), ham (RR: 1.44, 95% CI: 1.00-2.06), and sausage (RR: 1.33, 95% CI: 1.16-1.52). When conducted by study design, the association was significant in case-control studies (RR: 1.63, 95% CI: 1.33-1.99) but not in cohort studies (RR: 1.02, 95% CI: 0.90-1.17) for red meat.
   PLoS One, 2013 · checked 2026-09-24
6. bcpk-r2-07 · cross-sectional study
   From April 2023 to March 2025, a total of 358 raw pork products (166 livers, 96 kidneys, and 96 pork meat) from retail markets and slaughterhouses, 388 fecal samples from pig farms, and 110 serum samples from locally diagnosed HEV cases were collected. ... Overall, the detection rates of HEV RNA were 1.8% (3/166) in liver, 1.0% (1/96) in pork meat, and 6.5% (25/384) in pig feces, but not in kidney. ... all swine sequences (n = 26) were exclusively of the subtype HEV-4d, which clustered closely with local human HEV-4d strains and shared over 92% nucleotide identity
   Int J Food Microbiol, 2026 · checked 2026-09-24
7. bcpk-r2-02 · meta-analysis of observational studies
   Pooling the data on dietary cured meat intake of all types yielded an RR of 1.48 (1.20-1.83), suggesting a 48% increased risk of glioma development among adults ingesting high levels of cured meat. Analyzing brain tumor risk by meat type yielded an RR of 0.90 (0.63-1.25) for hotdogs (a nonstatistically significant result), 1.31 (1.00-1.71) for bacon, and 1.64 (1.27-2.14) for ham. Sensitivity analyses showed that the failure of most studies to adjust for total energy intake might lead to a spurious positive association between cured meat intake and brain tumor risk.
   J Environ Pathol Toxicol Oncol, 2003 · checked 2026-09-24
8. bcpk-r2-08 · meta-analysis of prevalence studies
   The pooled anti-HEV seroprevalence was estimated to be 5.68% (95% CI: 3.48-9.12%), with substantial heterogeneity. Country-specific estimates ranged from 1.01% in Greece to 26.66% in Bulgaria. ... However, meta-regression indicated that methodological and temporal factors, particularly serological assay type and year of publication, were the main significant moderators, whereas national pork consumption was not independently associated with seropositivity.
   Viruses, 2026 · checked 2026-09-24
9. bcpk-r2-05 · randomised controlled trial
   A pilot quasi-experimental study investigated whether provision of pork, a rich source of thiamin, as the main protein source in meals four times/week for 12 weeks resulted in improved muscle mass, body strength, and cognitive function in community-living older adults compared to similar meals containing chicken. ... Forty-eight volunteers participated (78.2 ± 6.2 y). ... Provision of four pork meals a week did not result in improvements in cognitive function, nor measures of strength or physical function, compared to those receiving chicken meals in healthy older adults.
   J Nutr Gerontol Geriatr, 2016 · checked 2026-09-24