Eating salads with plenty of raw vegetables such as baby kale, spinach, grated carrot or squash, radish etc. and then topping it with sliced boiled egg apparently improves the absorption of a nutrient in vegetables called ‘carotenoids’. Carotenoids need fat in order to get from the gut into the blood stream, and they exist in the colourful vegetables such as tomatoes (lycopene), carrots (beta-carotene), peppers(zeaxanthin) and spinach(lutein – also present in egg yolk!). The fat in egg yolks allows all of these nutrients to be better absorbed (up to 8 times more than if no egg was included) according to a study published by the American Journal of Clinical Nutrition and funded by the American Egg Board – Egg Nutrition Center.
Eggs also contain essential amino acids, unsaturated fat, and B vitamins and are great as part of balanced diet, however they are not fit for vegans or some vegetarians and there is no reason explained in this study why an egg should be used over other sources of fat, such as yoghurt, nut oils, avocado or any source of “good fats” that help the absorption of carotenoid; they argue that eggs are easier to portion control than oil-based salad dressings, but I cannot see many people using egg instead of a dressing! Eggs are a good source of protein, but so is meat and yoghurt. However, with oils and salad dressings, it is easy to use too much, making the overall calorie count for your meal relatively high. My personal tip is something you’d probably never think of – dollop yoghurt on your salad – nice creamy no-sugar-added natural Greek yoghurt! Not the zero fat stuff, but the whole fat. Two tablespoons = 20kcal, one egg = 70kcal. However, the egg does score better for protein.
The bottom line for me is, if you eat a lovely crisp salad with raw vegetables, don’t miss the oil! Carotenoids and other fat-soluble vitamins and nutrients need it. Just be mindful that fat carries more than double the calories of carbohydrates or protein.
References
[1] Sommerburg et al Fruits and vegetables that are sources for lutein and zeaxanthin: the macular pigment in human eyes. British Journal of Opthalmology, 1998; 82(8) 907-910
[2] Goodrow et al Consumption of one egg per day increases serum lutein and zeaxanthin concentrations in older adults without altering serum lipid and lipoprotein cholesterol concentrations. The Journal of Nutrition, 2006;136(10) 2519-2524
Seb is a writer and blogger of food and nutrition. He holds a bachelors and a masters degree in nutrition science, and has studied sports and exercise nutrition at postgraduate level. He specialises in plant-based nutrition and believes passionately that we can all live with a little less meat.
