Pork tenderloin: lean meat that lifts the iron you absorb from the rest of the meal

In a randomized trial of 45 young women, adding 1.8 oz (50 g) of pork loin to a single phytate-rich meal raised the non-heme iron absorbed from that meal by 44 percent, and 75 g raised it by 57 percent. The trial measured absorption from one labeled meal and did not measure iron status, and 25 g made no significant difference. Over 8 weeks in 47 adults aged 60 and over, a diet built on 5.7 oz (162 g) of lean pork a day raised ferritin by 7.0 ng/mL, less than the 15.7 ng/mL rise on a pulse-based diet matched for total iron. None of these trials singled out tenderloin. They used fresh lean pork cuts. In USDA data, 3.5 oz (100 g) of raw tenderloin carries 21.6 g protein and 0.87 g saturated fat, a figure that ranged from 0.49 to 1.6 g across only 8 samples with trim level not stated.

The numbers, per 3.5 oz (100 g)

As people eat it, per 3.5 oz (100 g)

How much is actually in it

• Raw pork tenderloin averages 21.6 g protein and under 1 g saturated fat per 3.5 oz (100 g) in USDA data, though saturated fat ranged from 0.49 to 1.6 g across 8 samples. — USDA Foundation Foods, 8 analyzed samples of raw boneless pork tenderloin (n = 8 samples) Evidence E source
  Per 100 g raw: protein 21.58 g (20.56-24.13), saturated fat 0.87 g (0.49-1.6), cholesterol 59.6 mg (56.7-61.8), iron 0.93 mg (0.775-1.08), potassium 397 mg (375-423)

What a real portion looks like

• A 1.1 oz (30 g) slice of cooked pork tenderloin gives about 40 calories and 7.4 g protein, and a cup of 4.8 oz (135 g) gives about 181 calories and 33 g protein. — US household measures, FNDDS (n = FNDDS portion weights) Evidence E source
  Per 100 g 134 calories, 24.65 g protein; 1 slice 30 g 40.2 calories 7.4 g protein; 1 cup 135 g 180.9 calories 33.3 g protein; default portion 2.1 oz (60 g)

What your body absorbs

• In 45 young women, adding 1.8 oz (50 g) of pork to a phytate-rich meal raised non-heme iron absorption by 44%, and 75 g raised it by 57%, while 25 g had no significant effect. — 45 healthy women, mean age 24, single labeled meals with 25, 50 or 75 g pork loin muscle (n = 45) Evidence B source
  Non-heme iron absorption +44% with 50 g, +57% with 75 g, 25 g not significant
• Over 5-day whole diets in 19 women, meals with 60 g pork raised non-heme iron absorption to 7.9% against 5.3% on a vegetarian diet with the same phytate and vitamin C. — 19 healthy women, 3 x 5-day controlled diets, 60 g pork per main meal (180 g/day) (n = 19) Evidence B source
  Fractional non-heme iron absorption 7.9% and 6.8% on pork diets vs 5.3% vegetarian

What cooking and storage change

• By the USDA retention table for roasted fresh pork, about 60% of thiamin, 80% of vitamin B12 and 85% of niacin remain after roasting, while iron and zinc stay at 100%. — USDA retention factor for Pork Products group, fresh, roasted; group-level, not tenderloin-specific (n = group factor) Evidence E source
  Retained: thiamin 60%, vitamin B12 80%, niacin 85%, vitamin B6 85%, iron 100%, zinc 100%
• In 21 women, pork cooked at 120 C still raised non-heme iron absorption from a meal by 2.0 percentage points, so higher cooking temperature did not remove the meat effect. — 21 women aged about 25, basic meal plus 75 g pork cooked at 70, 95 or 120 C (n = 21) Evidence B source
  Absorption +0.9, +0.7 and +2.0 percentage points with pork cooked at 70, 95 and 120 C

What it does to your health

• In a 6-month trial of 164 overweight adults, eating up to 2.2 lb (1 kg) of fresh lean pork a week in place of other foods reduced weight and fat mass compared with a habitual diet, in an industry-funded pilot whose abstract reports no effect sizes. — 164 overweight adults, mean BMI 32, men about 135 g and women about 97 g pork per day, 6 months (n = 164) Evidence B source
  Significant reductions in weight, BMI, waist, body fat and abdominal fat at 3 and 6 months vs control, sizes not in abstract; lean mass unchanged
• In a 9-month crossover trial of 49 overweight adults eating up to 2.2 lb (1 kg) a week of pork, beef or chicken for 3 months each, body fat changed the same with every meat. — 49 overweight or obese middle-aged Australians, three 3-month periods (n = 49) Evidence B source
  No difference in BMI or any adiposity marker between pork, beef and chicken
• A meta-analysis of 12 studies found that, in trials without calorie limits, pork intake was associated with 1.9 lb (0.86 kg) lower body weight. — 12 studies of adults, experimental and observational (n = 12 studies) Evidence C source
  Body weight -1.9 lb (95% CI 0.37 to 3.4; metric: -0.86 kg, 0.17 to 1.55), body fat -0.77% in trials without energy restriction

Safety, limits and interactions

• In a feeding trial of 36 adults eating 5.5 oz (156 g) a day of lean pork or chicken, pork raised blood TMAO no more than chicken did. — 36 healthy adults per protein, all food provided, Dietary Guidelines pattern (n = 36) Evidence B source
  Pork non-inferior to chicken for circulating TMAO and trimethylamine; lipids, inflammation markers similar
• A 2023-2025 survey in China found hepatitis E virus RNA in 1.0% of retail pork meat samples and 1.8% of pig livers. — 358 raw pork products from retail markets and slaughterhouses in Shandong, China (n = 358) Evidence C source
  HEV RNA in 1/96 pork meat (1.0%), 3/166 livers (1.8%), 0 kidneys
• USDA FSIS advises cooking raw pork roasts such as tenderloin to at least 145 °F (63 °C) and letting the meat rest for at least three minutes before carving or eating. — consumers cooking whole cuts of pork, USA Evidence E source
  145 °F plus a 3-minute rest

Who this works differently for

• In 33 adults at cardiovascular risk, a Mediterranean diet with 2 to 3 weekly serves of lean pork for 8 weeks gave the same blood pressure and lipids as a low-fat diet. — 33 adults aged 45-80 at risk of CVD, 8-week periods with washout (n = 33) Evidence B source
  No difference in blood pressure, lipids, glucose, insulin or CRP; low-fat diet lost 1.4 lb (0.65 kg) more
• In 47 adults aged 60 and over, a diet built on 162 g a day of lean pork raised ferritin by 7.0 ng/mL over 8 weeks, less than the 15.7 ng/mL rise on a pulse-based diet. — 47 Midwestern US adults aged 60+, 72% women, 8-week crossover periods (n = 47) Evidence B source
  Ferritin +7.0 ng/mL with pork diet vs +15.7 ng/mL with pulse diet, between-diet p = 0.027; both diets improved glucose and lipids

The bottom line

The weight results are weaker than they look. In a 6-month pilot trial of 164 overweight adults, eating up to 2.2 lb (1 kg) of fresh lean pork a week reduced weight and body fat against a habitual diet, but the abstract gives no sizes, the control group received no food, and the pork industry paid for it. When 49 overweight adults rotated pork, beef and chicken for 3 months each, body fat changed the same with every meat. A meta-analysis of 12 mixed studies put the effect in trials without calorie limits at 1.9 lb (0.86 kg) of body weight (95% CI 0.17 to 1.55). Read that as a lean protein that fits a diet about as well as beef or chicken. In 33 adults at cardiovascular risk, a Mediterranean diet with 2 to 3 weekly serves of lean pork gave the same blood pressure and lipids over 8 weeks as a low-fat diet. Roasting keeps all the iron and zinc by the USDA retention factor for fresh roasted pork, along with about 60 percent of thiamin and 80 percent of vitamin B12. That comes from a 1975 group table, not one measured on tenderloin. In 21 women, pork cooked at 120 C still enhanced iron absorption from a single meal. A 1.1 oz (30 g) slice of cooked tenderloin gives about 40 calories and 7.4 g protein, and the cooking method behind that figure is not specified. In a feeding trial of 36 healthy adults eating 5.5 oz (156 g) a day, lean pork raised blood TMAO no more than chicken did. That is a short-term biomarker from an industry-supported study. A 2023 to 2025 survey in Shandong, China found hepatitis E virus RNA in 1 of 96 retail pork meat samples and 3 of 166 pig livers. The survey detected RNA and did not test whether the virus was infectious, so it cannot tell you how often pork carries a live virus, and it is no reason to serve pork undercooked. We hold no card on a safe cooking temperature for pork, on who is most at risk from hepatitis E, or on pork allergy, pregnancy or drug interactions. That is a gap in our evidence, not a finding that there is nothing to watch for. If you are pregnant, have liver disease or a weakened immune system, ask your doctor how to cook and eat pork.

Sources

1. pktl-r1-01 · reference dataset
   FDC 2646169 Pork, loin, tenderloin, boneless, raw: Protein 21.58 g, range 20.56-24.13, n=8 · Fatty acids, total saturated 0.8663 g, range 0.49-1.6 · Cholesterol 59.58 mg, range 56.7-61.8 · Iron 0.9293 mg, range 0.775-1.08 · Potassium 397.4 mg, range 375.0-423.0
   USDA FoodData Central Foundation Foods, release 2026-04-30 · checked 2026-09-29
2. pktl-r1-02 · reference dataset
   FNDDS 2705877 Pork, tenderloin: Energy 134 kcal, Protein 24.65 g per 100 g · 1 slice, any size 30 g: 40.2 kcal, 7.4 g protein · 1 cup 135 g: 180.9 kcal, 33.3 g protein · Quantity not specified 60 g: 80.4 kcal, 14.8 g protein
   USDA FNDDS 2021-2023 · checked 2026-09-29
3. pktl-r1-04 · randomized controlled trial
   RESULTS: Twenty-five grams meat did not increase nonheme-iron absorption significantly (P = 0.13), whereas absorption increased 44% (P < 0.001) and 57% (P < 0.001), respectively, when 50 and 75 g meat were added to the basic meal.
   Am J Clin Nutr, 2003 · checked 2026-09-29
4. pktl-r1-05 · randomized crossover trial
   The mean fractional absorption of non-haem iron was 7.9 (se1.1), 6.8 (se 1.0) and 5.3 (se 0.6) % for the Danish and Polish meat diets and vegetarian diet, respectively.
   Br J Nutr, 2005 · checked 2026-09-29
5. pktl-r1-03 · reference dataset
   USDA-RETN-R6:1254 PORK,FRESH,ROASTED: thiamin_mg 60% · vitamin_b12_ug 80% · niacin_mg 85% · vitamin_b6_mg 85% · iron_mg 100% · zinc_mg 100%
   USDA Table of Nutrient Retention Factors, Release 6 (2007) · checked 2026-09-29
6. pktl-r1-06 · randomized controlled trial
   Increasing the cooking temperature of meat did not impair nonheme iron absorption compared with cooking at 70 degrees C.
   J Nutr, 2003 · checked 2026-09-29
7. pktl-r1-07 · randomized controlled trial
   After 3 months, there were significant (p ≤ 0.01) reductions in weight, BMI, waist circumference, % body fat, fat mass and abdominal fat in the pork group relative to controls, which persisted for 6 months.
   Nutrients, 2012 · checked 2026-09-29
8. pktl-r1-08 · randomized crossover trial
   There was no difference in BMI or any other marker of adiposity between consumption of pork, beef and chicken diets.
   Nutrients, 2014 · checked 2026-09-29
9. pktl-r1-09 · meta-analysis
   Among the experimental studies without daily total energy intake restrictions, pork intake was associated with a reduction in body weight by 0.86 kg (95% CI = 0.17-1.55) and body fat percentage by 0.77% (95% CI = 0.11%-1.43%); pork intake was not associated with change in lean mass.
   Am J Health Behav, 2020 · checked 2026-09-29
10. pktl-r1-10 · randomized crossover trial
    Mixed-effect modeling shows pork as noninferior to chicken for circulating TMAO response and microbiota-generated essential TMAO-precursor-trimethylamine (97.5% CI, n = 36/protein).
    Mol Nutr Food Res, 2022 · checked 2026-09-29
11. pktl-r1-13 · cross-sectional survey
    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.
    Int J Food Microbiol, 2026 · checked 2026-09-29
12. sf-fsis-r4-2 · agency advice
    Cook all raw beef, pork, lamb, and veal steaks, chops, and roasts to a minimum internal temperature of 145 °F...For safety and quality, allow meat to rest for at least three minutes before carving or consuming.
    USDA FSIS, Doneness Versus Safety · checked 2026-10-08
13. pktl-r1-11 · randomized crossover trial
    No significant differences were observed for blood pressure, lipids, glucose, insulin or CRP.
    Br J Nutr, 2019 · checked 2026-09-29
14. pktl-r1-12 · randomized crossover trial
    PPD demonstrated a larger increase in ferritin relative to MPD (PPD: +15.7 ng/mL vs. MPD: +7.0 ng/mL; between-diet p = 0.027), and CRP decreased in both groups (both, p ≤ 0.001, no between-diet differences).
    Clin Nutr ESPEN, 2026 · checked 2026-09-29