Beef and beef and broccoli: cholesterol level with chicken, iron on paper

In a meta-analysis of 8 randomized trials with 406 adults free of chronic disease, diets with beef lowered LDL cholesterol by 8.2 mg/dL from baseline, against 8.9 mg/dL with poultry or fish, and the gap was not significant. Those trials are old and used lean beef in controlled diets, so they say nothing about processed meat or heart attacks. Raw beef carries 1.6 to 2.5 mg of iron per 3.5 oz (100 g) depending on the cut, and 3.2 to 5.6 mg of zinc, measured on 8 US retail samples per cut. Whether that iron changes your blood is less clear. In 52 women with low iron stores taking a 32 mg iron supplement with lunch for 8 weeks, 4 oz (113 g) of beef alongside raised ferritin no more than a plant-based burger did, and the supplement dose dwarfed the iron in the meat. For beef and broccoli as a dish we have a portion weight, 217 g per cup in US survey data, and we found no study of the stir-fry itself.

How much is actually in it

• Iron in raw beef varies by cut from about 1.6 mg per 3.5 oz (100 g) in ribeye and strip steak to 2.5 mg in tenderloin, and zinc from about 3.2 mg in tenderloin to 5.6 mg in flank. — USDA Foundation Foods raw beef cuts, 8 samples each (n = 8 samples per cut) Evidence E source
  Iron 1.608-2.53 mg/100 g across cuts; zinc 3.225-5.563 mg/100 g

What a real portion looks like

• A cup of beef and broccoli stir-fry weighs 7.7 oz (217 g) in US survey portions, and an unspecified serving of ground beef is 85 g. — US household measures, FNDDS Evidence E source
  Beef and broccoli 1 cup 217 g, quantity not specified 163 g; ground beef quantity not specified 85 g

What your body absorbs

• In an 8-week RCT in 52 women with low iron stores (serum ferritin below 25 ug/L), taking a 32 mg iron supplement with 4 oz (113 g) of beef raised ferritin no more than taking it with a plant-based burger (ferritin rose about 10.7 ug/L in both). — 52 nonpregnant women of reproductive age, serum ferritin below 25 ug/L, 8 weeks (n = 52) Evidence B source
  Ferritin +10.7 ± 9.6 ug/L over time, treatment-by-time interaction P > 0.05 for all iron indicators
• In absorption studies in 45 women, heme iron absorption (10.3% alone) fell when mixed with fish (7.1%) or chicken (4.9%) but was unaffected by beef. — 45 women aged 35-45 years, three randomized absorption sub-studies (n = 45) Evidence B source
  Heme iron absorption 10.3% alone vs 7.1% with fish and 4.9% with chicken (p<0.05), beef no change
• Laboratory data suggest the meat factor in beef that boosts nonheme iron absorption is at least partly L-alpha-glycerophosphocholine, identified from digested lean beef in Caco-2 cells. — digested cooked ground beef in Caco-2 cells; confirmation meal in 13 women with low iron stores used the isolated compound, not beef (n = 13) Evidence D source
  Compound added to vegetarian lasagna raised nonheme iron absorption (P = 0.023)

What cooking and storage change

• Laboratory measurements pooled from 28 studies show cooking raises carcinogenic PAH4 in beef, most with smoking and with coal or wood fuel at high heat. — beef and beef products analyzed in 28 laboratory studies (n = 28 articles) Evidence D source
  PAH4 higher in thermally processed beef, g' = 1.64 (P < 0.001); smoking above grilling, g' > 0.8
• By the USDA retention table for broiled beef cuts, vitamin B6 loses the most (60% kept), thiamin keeps 70% and B12 80%, while iron keeps 95% and zinc 100%. — USDA retention factors for Beef Products, broiled cut Evidence E source
  B6 60%, thiamin 70%, B12 80%, niacin 80%, iron 95%, zinc 100% retained

What it does to your health

• In a meta-analysis of 8 RCTs with 406 adults, eating beef lowered LDL cholesterol about as much as poultry or fish (-8.2 vs -8.9 mg/dL from baseline, no significant difference). — 8 RCTs, 406 subjects free of chronic disease, published 1950-2010 (n = 406) Evidence A source
  LDL -8.2 ± 4.2 vs -8.9 ± 4.4 mg/dL (P = .905); total cholesterol -8.1 vs -6.2 mg/dL (P = .630)

Safety, limits and interactions

• In a 3-phase crossover trial in 15 healthy adults, a week of beef gave the highest calcium oxalate saturation index (2.48 vs 1.67 for chicken), while fish raised urinary uric acid most. — 15 healthy subjects, 1-week phases of beef, chicken or fish metabolic diet (n = 15) Evidence B source
  CaOx saturation 2.48 beef vs 1.67 chicken (p = 0.02) vs 1.79 fish (p = 0.08)
• Survey data pooled from 33 studies find Salmonella in 10.8% of cattle deep lymph nodes, which end up in ground beef trimmings. — bovine deep tissue lymph nodes, 33 studies (n = 33 studies) Evidence C source
  Pooled prevalence 10.8% (95% CI 7.5-14.5); warm season 10.7% vs cool 3.8%
• Alpha-gal syndrome, a tick-borne allergy to a sugar in mammalian meat, can cause severe reactions to beef, as one case report describes. — one 53-year-old man with alpha-gal syndrome (n = 1) Evidence D source
  Severe sensitivity to beef, lower reactivity to pork
• USDA FSIS says a hamburger is safe once it reaches 160 °F (71 °C) measured with a food thermometer throughout the patty, whatever its color, because ground beef can turn brown before bacteria are destroyed. — consumers cooking ground beef, USA Evidence E source
  160 °F for ground beef; color not a safe indicator

What people believe that the data does not support

• The EU has authorized no health claim for beef. A claim that omega-3 enriched beef and other animal products help regulate carbohydrate metabolism was non-authorized. — EU Register on nutrition and health claims, snapshot 2026-09-21 Evidence E source
  0 authorized, 2 non-authorized claims naming beef

Who this works differently for

• In a crossover RCT in 23 calcium stone formers, two daily servings of beef gave the same urinary stone risk index as the same protein from plants. — 23 normocalciuric patients with a history of calcium kidney stones (8 women, 15 men), 4-day adaptation plus 2-day metabolic unit (n = 23) Evidence B source
  Urinary calcium, oxalate, citrate and Tiselius risk index did not differ between diets
• In a crossover feeding RCT in 17 breastfeeding women, 6 days of 339 g beef a day gave breast milk more arachidonic acid (0.41 vs 0.35%) than a plant-based beef substitute. — 17 lactating women exclusively breastfeeding, two 6-day diet phases (n = 17) Evidence B source
  Milk arachidonic acid 0.41 ± 0.06 vs 0.35 ± 0.06% (P < 0.001); lauric acid 4.47 vs 9.32%

What is still unknown

• Whether beef affects thinking and memory is largely unstudied: a scoping review found 22 studies, only 6 on beef itself, most at high risk of bias. — 22 intervention and observational studies up to March 2022, children to seniors (n = 22 studies) Evidence C source
  6 of 22 studies assessed beef specifically; majority rated high or serious risk of bias

The bottom line

Cooking changes what is left. By the USDA retention table for broiled beef, iron keeps 95 percent and zinc all of it, while vitamin B6 drops to 60 percent and B12 to 80 percent. That is a group factor from a 1975 table and was never measured on a stir-fry. Laboratory data pooled from 28 studies show that heat raises the carcinogenic PAH4 group in beef, and smoking raises it more than grilling. This is food chemistry with no human outcome attached. Iron absorption from a mixed meal behaves oddly. In isotope studies in 45 women, blending heme iron with fish or chicken cut its absorption from 10.3 percent to 7.1 and 4.9 percent, and blending it with beef left it unchanged. Laboratory work traces part of beef's boost to plant iron to a compound called L-alpha-glycerophosphocholine, though beef itself was not fed in the human part of that study. Who should be careful. Alpha-gal syndrome, a tick-borne allergy to a sugar found in mammalian meat, can make beef cause severe reactions. The evidence here is a single case report, which shows the allergy exists and says nothing about how common it is. Survey data from 33 studies found Salmonella in 10.8 percent of cattle deep lymph nodes (95% CI 7.5 to 14.5), and those nodes end up in ground beef trimmings. That figure measures how often the nodes are contaminated, not how often people fall ill, and it does not make undercooked ground beef safe. USDA FSIS counts a hamburger as safe once it reaches 160 °F (71 °C), measured with a food thermometer throughout the patty, whatever its color, because ground beef can turn brown before bacteria are destroyed. Two small trials on kidney stones measured urine rather than stones. In 15 healthy adults, one week of beef gave the highest calcium oxalate saturation index, 2.48 against 1.67 for chicken. In 23 people who had already had calcium stones, two daily servings of beef gave the same urinary risk index as the same protein from plants. In 17 breastfeeding women, 12 oz (339 g) of beef a day for 6 days put more arachidonic acid into breast milk than a plant-based substitute, 0.41 against 0.35 percent, and no infant outcome was measured. Whether beef affects thinking or memory is largely unstudied: a scoping review found 22 studies, only 6 on beef itself, most at high risk of bias. The EU has authorized no health claim for beef.

Sources

1. bfbr-r6-12 · reference dataset
   Beef, tenderloin steak, raw: Iron 2.53 mg, range 2.12-2.82, n=8; Zinc 3.225 mg, range 2.71-3.72, n=8 · Beef, short loin (NY strip steak), raw: Iron 1.608 mg, range 1.23-2.27, n=8 · Beef, ribeye, steak, boneless, choice, raw: Iron 1.641 mg, n=8 · Beef, flank, steak, boneless, choice, raw: Zinc 5.563 mg, range 4.9-6.49, n=8
   USDA FoodData Central Foundation Foods, release 2026-04-30 · checked 2026-09-28
2. bfbr-r6-13 · reference dataset
   FNDDS 2706738 Beef and broccoli (code 27415110): 1 cup 217 g · Quantity not specified 163 g · FNDDS 2705854 Beef, ground (code 21500100): Quantity not specified 85 g · 1 cup 125 g
   USDA FNDDS 2021-2023 · checked 2026-09-28
3. bfbr-r6-02 · randomized controlled trial
   nonpregnant females of reproductive age (n = 52; 24 ± 7 y; body mass index 22.9 ± 3.0 kg/m2) with low iron stores (serum ferritin concentration <25 μg/L) were randomly assigned to consume an iron supplement containing 32 mg elemental iron (from ferrous sulfate) with a lunch meal containing either 4 oz. (113 g) of 1) beef (Animal) or 2) Beyond Meat (Plant) once a day for 8 wk ... improved serum ferritin concentrations (main time effect: +10.7 ± 9.6 μg/L, P < 0.0001)
   Am J Clin Nutr, 2025 · checked 2026-09-28
4. bfbr-r6-03 · randomized controlled trial
   Forty-five women (35-45 year) were randomly assigned to three iron (Fe) absorption sub-studies ... Study 2: the bioavailability from heme alone (10.3%) was reduced (p<0.05) when it was blended with fish (7.1%) and chicken (4.9%), however it was unaffected by beef.
   Food Chem, 2016 · checked 2026-09-28
5. bfbr-r6-04 · in vitro and human absorption study
   Lean beef was selected for study, as it is known to increase nonheme iron absorption. ... We have identified L-alpha as a component of muscle tissue that enhances nonheme iron absorption
   J Nutr, 2008 · checked 2026-09-28
6. bfbr-r6-08 · meta-analysis of laboratory studies
   A meta-analysis of 28 articles indicated that thermally processed beef had significantly higher PAH4 levels than did the control beef (g' = 1.64; P < 0.001). Smoking caused greater PAH4 buildup than did grilling and barbecuing (g' > 0.8; P < 0.001).
   Meat Sci, 2026 · checked 2026-09-28
7. bfbr-r6-11 · USDA Table of Nutrient Retention Factors, dataset
   USDA-RETN-R6:602 BEEF,BROILED CUT, group Beef Products: vitamin_b6_mg 60% retained, thiamin_mg 70%, vitamin_b12_ug 80%, niacin_mg 80%, iron_mg 95%, zinc_mg 100%
   USDA Table of Nutrient Retention Factors, Release 6, 2007, Retn_Code 602 · checked 2026-09-28
8. bfbr-r6-01 · meta-analysis of randomized controlled trials
   8 studies involving 406 subjects met the prespecified entry criteria and were included in the analysis ... -8.2 ± 4.2 vs. -8.9 ± 4.4 for low-density lipoprotein cholesterol (P = .905) ... Changes in the fasting lipid profile were not significantly different with beef consumption compared with those with poultry and/or fish consumption.
   J Clin Lipidol, 2012 · checked 2026-09-28
9. bfbr-r6-06 · randomized controlled trial
   A total of 15 healthy subjects completed a 3-phase randomized, crossover metabolic study. ... Mean saturation index for calcium oxalate was highest for beef (2.48), although the difference attained significance only compared to chicken (1.67, p = 0.02) but not to fish (1.79, p = 0.08).
   J Urol, 2014 · checked 2026-09-28
10. bfbr-r6-09 · systematic review and meta-analysis of prevalence studies
    Bovine deep tissue lymph nodes (DTLNs) are retained in bench trimmings during carcass fabrication and enter the ground beef supply ... The pooled Salmonella prevalence in DTLNs was 10.8% (95% CI [7.5, 14.5]), with significant heterogeneity between studies.
    Int J Food Microbiol, 2026 · checked 2026-09-28
11. bfbr-r6-10 · case report
    Alpha-gal syndrome (AGS) is a tick-borne allergic condition triggered by galactose-alpha-1,3-galactose, a carbohydrate found in mammalian products. ... The patient exhibited severe sensitivity to beef but lower reactivity to pork products
    J Am Pharm Assoc (2003), 2025 · checked 2026-09-28
12. sf-fsis-1 · agency advice
    Ground beef may turn brown before it has reached a temperature at which bacteria are destroyed. ...A hamburger cooked to 160 °F (165 °F for ground poultry), measured with a food thermometer throughout the patty...is safe — regardless of color.
    USDA FSIS, Doneness Versus Safety · checked 2026-10-08
13. bfbr-r6-14 · regulatory decision
    POL-HC-7872 Raw or processed food products of animal origin, plus bread and panification products (cow’s, goat’s and ewe’s milk and related products ( milk, cream, butter, cheese, yoghurt, fresh dairy products); hen’s and quail’s eggs; beef’s, veal’s and lamb’s me * The Tradilin network makes it possible to obtain products which fit into a diet naturally rich in omega 3 which participates to improve/decrease carbohydrate metabolic disorders La filière Tradilin permet d’obtenir des produits qui s’intègrent dans une alimentation riche en Oméga 3 qui participe diminuer les désordres du métabolisme des carbohydrates * The Tradilin network makes it possible to obtain products which fit into a diet naturally rich in omega 3 which participates in the control of parameters of the metabolic syndrome La filière Tradilin permet d’obtenir des produits qui s’intègrent dans une alimentation riche en Oméga 3 qui participe au contrôle des paramètres du syndrome métabolique * This product participates/contributes/helps to regulate carbohydrate metabolism Ce produit participe à la régulation du métabolisme glucidique * This product, from the Tradilin network, helps to better to regulate carbohydrate metabolism/ control the parameters on the metabolic syndrome Ce produit, issu de la filière Tradilin, s’intègre dans une alimentation riche en Oméga 3 qui participe à diminuer les désordres du métabolisme des carbohydrates/à contrôler les paramètres du syndrome métabolique Non-authorised
    EU Register on nutrition and health claims, claim POL-HC-7872, snapshot 2026-09-21 · checked 2026-09-28
14. bfbr-r6-05 · randomized controlled trial
    Twenty-three normocalciuric patients with a history of calcium kidney stones ... The study compared consumption of 2 servings of beef (43 g protein for women and 50 g for men) daily with an equal amount of protein from plant foods including legumes, nuts, and grains. ... Urinary calcium, oxalate, magnesium, citrate, phosphorus, volume, and TRI did not differ between diets.
    J Am Diet Assoc, 2001 · checked 2026-09-28
15. bfbr-r6-07 · randomized controlled trial
    17 lactating females whose infants were fed only their milk completed 2 6-d diet phases separated by 6-d washout periods. Participants consumed 339 g (12 oz) daily of beef or plant-based substitute, depending on the diet phase. ... lower levels of long-chain polyunsaturated fatty acids (LCPUFAs), including arachidonic acid (20:4n-6: 0.35 ± 0.06 compared with 0.41 ± 0.06, P < 0.001) compared with milk form the beef diet.
    Am J Clin Nutr, 2026 · checked 2026-09-28
16. bfbr-r6-15 · scoping review
    Twenty-two studies were identified that quantified beef or red meat intake and assessed cognition. Six studies assessed beef intake, with the remaining studies describing intake of red meat that may or may not include beef. ... Red meat and beef intake and cognition is largely understudied.
    Public Health Nutr, 2023 · checked 2026-09-28