Mayonnaise: the oil decides, the raw egg is the risk

Mayonnaise is oil held together by egg yolk, and nearly everything on this page follows from that. A 14 g tablespoon of the regular kind is about 94 kcal, and 100 g in USDA is 680 kcal with 74.85 g of fat. One crossover trial compared two mayonnaises that differed in their oil, and the oil was what moved the blood lipids: 20 g a day of soybean-oil mayonnaise for 4 weeks lowered total cholesterol by 0.25 mmol/L and LDL by 0.17 mmol/L against palm-olein mayonnaise. It lowered HDL by 0.12 mmol/L at the same time, so the ratio between the two did not move. The raw egg is where the risk sits. In two outbreak investigations, one at a UK charity event and one at a Sydney barbecue, egg mayonnaise was the food most tied to salmonella, and the Sydney batch was made with raw egg. FDA says that any dish served with raw egg, homemade mayonnaise among them, should be made with shell eggs treated to destroy Salmonella or with a pasteurised egg product. The one thing mayonnaise does for a vegetable is help its carotenoids across. In two small crossover trials, carrot and broccoli eaten with mayonnaise put more beta-carotene into the blood than the vegetable alone. One trial on this page fed people a plant-sterol mayonnaise built as a cholesterol-lowering product. That is a different thing from the jar in your fridge, and its result says nothing about ordinary mayonnaise.

The numbers, per 100 g

How much is actually in it

• Regular mayonnaise is 680 kcal, 74.85 g fat and 635 mg sodium per 100 g in USDA. The two reduced-fat jars are 333-361 kcal with 733-800 mg sodium. The low-sodium diet product is 231 kcal with 110 mg, and homemade mayonnaise in CoFID is 786 kcal with only 19 mg sodium. — USDA SR Legacy 171009 regular, 171443 reduced fat with olive oil, 168094 reduced-calorie, 168115 low sodium low calorie; CoFID 2021 code 17-809 homemade (n = 5 records) Evidence E source
  Energy 231-786 kcal, fat 19.2-84.2 g, sodium 19-800 mg, vitamin K 24.7-163 ug per 100 g across products

What a real portion looks like

• A tablespoon of regular mayonnaise is 14 g in USDA survey measures, about 94 kcal and 23 ug vitamin K, and a single-serve packet is 12 g. — US household measures, FNDDS Mayonnaise, regular (fdc_id 2710204); Mayonnaise, light (fdc_id 2710220) 1 tablespoon 15.6 g Evidence E source
  1 tablespoon 14 g = 93.8 kcal, about 89 mg sodium, about 23 ug vitamin K (recalculated from 680 kcal, 635 mg, 163 ug per 100 g); 1 packet 12 g = 81.6 kcal; guideline amount on a sandwich 16 g

What your body absorbs

• In 9 men eating grated carrot four ways in random order, carrot with mayonnaise gave a larger 8-hour rise in serum beta-carotene than carrot alone or carrot juice. — 9 healthy adult men, randomised crossover, carrot alone, carrot juice, carrot with oil, carrot with mayonnaise, blood at 2-8 h; plus rat and in vitro work (n = 9) Evidence B source
  Serum beta-carotene iAUC higher after mayonnaise than after carrot alone and carrot juice; oil arm not reported as different
• In 18 healthy adults, broccoli eaten with mayonnaise raised serum lutein/zeaxanthin and beta-carotene at 2, 4 and 6 hours, with a larger 6-hour area under the curve than broccoli alone. — 18 healthy adults, randomised crossover, broccoli alone, with oil, or with mayonnaise, serum carotenoids at 2, 4, 6 h (n = 18) Evidence B source
  IAUC of lutein/zeaxanthin and beta-carotene higher after mayonnaise meal than control; plain oil not significantly different from either

What cooking and storage change

• FDA advises that recipes served with raw or undercooked egg, the category homemade mayonnaise falls into, be made with eggs treated to destroy Salmonella or with pasteurized egg products. — US home cooks preparing raw-egg dishes Evidence E source
  Use shell eggs treated to destroy Salmonella, by pasteurization or another approved method, or pasteurized egg products, for recipes served with raw or undercooked egg

What it does to your health

• Eating 20 g a day of soybean-oil mayonnaise for 4 weeks lowered total cholesterol by 0.25 mmol/L and LDL by 0.17 mmol/L compared with palm-olein mayonnaise, but also lowered HDL by 0.12 mmol/L. The oil in the jar decides the effect. — Adults in a double-blind randomised crossover trial, 20 g/day mayonnaise for 4 weeks per arm with 2-week washout, Malaysia Evidence B source
  TC -0.25 mmol/L (P = 0.001), LDL-C -0.17 (P = 0.016), HDL-C -0.12 (P < 0.001); LDL:HDL ratio and small LDL unchanged

Safety, limits and interactions

• A 2-week double-blind trial of a plant-sterol and diacylglycerol mayonnaise at 1.2 g sterol ester in 30 g a day found no change in serum retinol, alpha-tocopherol or beta-carotene versus a plain triacylglycerol mayonnaise. — Healthy and mildly hypercholesterolaemic adults, randomised placebo-controlled double-blind parallel trial, 2 weeks Evidence B source
  No change in serum retinol, alpha-tocopherol, beta-carotene, abdominal symptoms, haematology or biochemistry
• In a 2006 UK charity-event outbreak of Salmonella Enteritidis, people who ate egg-mayonnaise bagels had 34 times the odds of diarrhoea (49 cases, 128 controls), with contaminated eggs the most likely cause. — Attendees of a children's charity event, Hertsmere, UK, June 2006; 49 cases and 128 controls (n = 177) Evidence C source
  Egg mayonnaise bagels OR 34.1 (95% CI 10.5-111.3); apple juice OR 16.1; no food samples available
• At a 2009 Sydney barbecue, 71 of 87 identified attendees fell ill with Salmonella Typhimurium and raw-egg mayonnaise in a Russian salad was the most likely vehicle (adjusted OR 10.3). 18% of cases were hospitalised. — 87 identified attendees of a community barbecue cooked by an unregistered family, Sydney, January 2009 (n = 87) Evidence C source
  71 cases (30 laboratory-confirmed), 76% sought medical care, 18% admitted; raw egg mayonnaise aOR 10.3 (95% CI 1.79-59.5)

What is still unknown

• Whether mayonnaise beats plain oil for carotenoid absorption is unresolved: in the 18-person broccoli trial the oil meal was not significantly different from either the control or the mayonnaise meal. — 18 healthy adults, randomised crossover, broccoli with oil versus with mayonnaise versus alone (n = 18) Evidence B source
  IAUC after oil meal: no statistically significant difference from control or mayonnaise

The bottom line

If you use mayonnaise, use the oil you would choose anyway. In the one trial that compared two mayonnaises, the oil was the thing that differed and the blood lipids followed it. Twenty grams a day, not much more than one tablespoon, was enough to move them in 4 weeks, LDL and HDL together. The abstract does not say how many people were in that trial. Reduced- fat jars are a trade rather than a saving. In USDA the two reduced-fat jars are 333 to 361 kcal per 100 g and carry 733 to 800 mg of sodium, against 635 mg in the regular kind. The separate low-sodium diet product is 231 kcal with 110 mg, so read the label rather than the word light. Homemade mayonnaise in the British tables has 19 mg of sodium and 786 kcal, and it carries the raw egg. FDA advice for any dish served with raw egg is to make it with pasteurised shell eggs or pasteurised egg product. The two outbreaks here show what the failure looks like. At the Sydney barbecue 71 of 87 people fell ill and 18 percent of the cases went to hospital. Those are investigations after the fact, with wide confidence intervals and no food samples in the UK case, so they say what happened once and cannot tell you how often it happens. The carotenoid finding is real and small. In 9 men, grated carrot eaten with mayonnaise raised serum beta-carotene over 8 hours more than carrot alone or carrot juice. In 18 adults, broccoli with mayonnaise did the same for lutein and beta- carotene over 6 hours. Whether the mayonnaise does anything plain oil would not is unresolved: in the broccoli trial the oil meal was not significantly different from the vegetable alone or from the mayonnaise. Both trials were small and measured blood over hours rather than health over years. Mayonnaise is also a vitamin K food, 163 micrograms per 100 g in the regular jar and about 23 in a tablespoon. People taking warfarin and similar anticoagulants need a consistent vitamin K intake rather than a low one: sudden changes in either direction can increase or decrease the effect of the medicine. What this page cannot tell you is who should stay away. We have no card on egg allergy, on pregnancy, or on any drug that mayonnaise interacts with, and the salmonella advice above is the only caution we can cite. That is a gap in our research. It does not mean no caution is needed.

Sources

1. mayo-c2-08 · reference dataset
   SR Legacy 171009 Salad dressing, mayonnaise, regular: energy 680 kcal, fat 74.85 g, saturated 11.703 g, sodium 635 mg, vitamin K 163 ug, vitamin E 3.28 mg || 171443 Mayonnaise, reduced fat, with olive oil: 361 kcal, fat 40 g, sodium 800 mg, vitamin K 53.7 ug || 168094 Mayonnaise, reduced-calorie or diet, cholesterol-free: 333 kcal, fat 33.3 g, sodium 733 mg || 168115 Mayonnaise, low sodium, low calorie or diet: 231 kcal, fat 19.2 g, sodium 110 mg || CoFID 17-809 Mayonnaise, homemade: 786 kcal, fat 84.2 g, sodium 19 mg, vitamin E 4.40 mg per 100 g
   USDA FoodData Central SR Legacy (published 2019-04-01) and CoFID 2021, Public Health England / OGL v3.0 · checked 2026-09-23
2. mayo-c2-09 · reference dataset
   Mayonnaise, regular [2710204] Energy 680 KCAL per 100 g, 1 tablespoon 14 g 93.8 KCAL, 1 packet 12 g 81.6 KCAL, 1 cup 220 g 1496.0 KCAL || Sodium, Na 635 MG per 100 g || Vitamin K (phylloquinone) 163 UG per 100 g || Mayonnaise, light [2710220] 1 tablespoon 15.6 g, guideline amount on regular sandwich 16 g
   USDA FoodData Central survey foods (FNDDS) 2024-10-31, fdc_id 2710204 · checked 2026-09-23
3. mayo-c2-02 · RCT
   Following collection of fasting blood samples, nine adult males consumed one of the four diets in random order. ... The incremental areas under the curves of serum β-carotene concentration were higher following MS than following both CON and JU.
   J Nutr Sci Vitaminol (Tokyo), 2011 · checked 2026-09-23
4. mayo-c2-03 · RCT
   Eighteen healthy subjects participated in the test, which consisted of broccoli as a control (CON) meal, broccoli with oil (OIL), and broccoli with mayonnaise (MS), consumed in random order. ... The incremental areas under the curves (IAUCs) of serum lutein/zeaxanthin and beta-carotene concentrations were higher after the MS meal than after the CON meal.
   J Nutr Sci Vitaminol (Tokyo), 2009 · checked 2026-09-23
5. mayo-c2-07 · guidance
   For recipes that call for eggs that are raw or undercooked when the dish is served — like Caesar salad dressing and homemade ice cream — use either shell eggs that have been treated to destroy Salmonella, by pasteurization or another approved method, or pasteurized egg products.
   FDA, What You Need to Know About Egg Safety (page dated 2024-03-05) · checked 2026-09-23
6. mayo-c2-01 · RCT
   consuming diets supplemented with 20 g/day of either soybean oil-based mayonnaise (SB-mayo) or palm olein-based mayonnaise (PO-mayo) for 4 weeks each with a 2-week wash-out period. ... Treatments resulted in significant reductions in TC (diff = -0.25 mmol/L; P = 0.001), LDL-C (diff = -0.17 mmol/L; P = 0.016) and HDL-C (diff = -0.12 mmol/L; P < 0.001) in SB-mayo compared to PO-mayo
   Lipids Health Dis, 2016 · checked 2026-09-23
7. mayo-c2-04 · RCT
   the subjects ingested 1.2 g PSE/30 g DAG for 2 weeks in the form of mayonnaise-type products. Triacylglycerol (TAG) mayonnaise was used as a control. RESULT: There were no subjective adverse effects or changes in serum retinol, alpha-tocopherol, and beta-carotene levels, abdominal symptoms, hematologic values, or blood biochemical values.
   Ann Nutr Metab, 2006 · checked 2026-09-23
8. mayo-c2-05 · case-control
   Information was available for 49 cases and 128 controls (overall response rate=75%). ... Risk factors for diarrhoea were eating egg mayonnaise bagels (OR=34.1, 95%CI 10.5 - 111.3) and drinking apple juice (OR=16.1, 95% CI 3.5 - 74.2).
   Euro Surveill, 2007 · checked 2026-09-23
9. mayo-c2-06 · cohort
   Seventy one of the 87 attendees identified met the case definition. ... with the raw egg mayonnaise used in a Russian salad being the most likely primary food vehicle (adjusted odds ratio=10.3 [95% confidence interval 1.79-59.5]).
   Foodborne Pathog Dis, 2011 · checked 2026-09-23
10. mayo-c2-10 · RCT
    IAUCs after the OIL meal exhibited no statistically significant differences from the CON and MS meals.
    J Nutr Sci Vitaminol (Tokyo), 2009 · checked 2026-09-23