How Many Eggs Per Week?

cooked egg

An interesting study, dubbed the DIABEGG trial, explored whether overweight people with type 2 diabetes would benefit from eating more eggs to boost satiety and improve weight management. The only concern was – would their cholesterol levels climb through the roof?

Although an average hen’s egg contains around 200mg cholesterol, their total fat content isn’t high (5.2 g) and is predominantly in the form of monounsaturated fats (51%) or polyunsaturated fats (16%) rather than the saturated fats which are widely demonised (although steadily gaining admirers).




ExamThe DIABEGG study involved 140 Australians, with an average age of 60 and an average BMI of 34 (obese), who also had poor glucose tolerance (prediabetes) or type 2 diabetes. Half were randomly assigned to eat 12 eggs a week (two for breakfast on six days out of seven) for 3 months while the other half were asked to match the protein intake of the high egg group by eating 10g lean protein from meat, chicken, fish, legumes or reduced-fat dairy products for breakfast but to eat less than 2 eggs a week.

At the beginning of the study, there were no significant differences between the two groups in age, fasting glucose, glucose control (as measured by HbA1c), blood pressure or total body fat, although those in the high egg group weighed an average of 98kg versus 93.3kg for those in the low-egg group. Both groups were instructed to maintain their body weight which they successfully managed to do (gaining or losing less than 1kg on average).

At the end of the study, there were no significant differences between the two groups in their levels of total cholesterol, ‘bad’ LDL-cholesterol, ‘good’ HDL-cholesterol or triglycerides. This was despite the fact that food diary analysis showed those eating 12 eggs a week increased their total daily cholesterol intake by  281mg, compared with a reduction of -36mg cholesterol for those on the low-egg diet, giving an average difference between the two groups of 337mg dietary cholesterol intake per day.

But wait a minute …

Why Didn’t Their Lipids Change?

At first sight, these findings seem extraordinary. Eating 12 eggs a week didn’t raise blood cholesterol levels any more than a similar group eating less than two eggs a week. Really?

Much as I like eggs, and would love to pounce on this fabulous finding with glee, the baseline total cholesterol levels of both groups were also extraordinarily good. Almost too good to be true, in fact: total cholesterol 5 mmol/L or less; LDL cholesterol 2.9 mmol/L or less, HDL cholesterol 1.2 mmol/L or greater and triglycerides not too shabby at 1.8 mmol/L or lower, on average.

Diabegg_study

Source: Fuller NR et al. Am J Clin Nutr. 2015 Apr;101(4):705-13.

These are stunning baseline results, given that only 56% of those assigned to the high-egg group and 52% of those allocated to the low egg group were taking a statin. I’ll say that again. Only 56% of those assigned to the high-egg group were taking a statin. Statins are usually dished out like Smarties to people who are obese with type 2 diabetes or prediabetes. If they’re not on a statin yet have pretty perfect lipid profiles, what’s going on?

The most likely explanation is that almost half the 140 people in the DIABEGG trial happen to have inherited cholesterol-friendly genes. If you inherit ‘good’ genes, the amount of LDL-cholesterol that’s synthesised by your liver reduces as your dietary intake of cholesterol increases. If you inherit ‘bad’ genes, on the other hand, this negative feedback mechanism malfunctions, so your liver keeps continues churning out cholesterol even though you get plenty in your diet, and have plenty in your circulation.

Maybe this part of Australia is different

As all these study volunteers were recruited from around Sydney, capital of New South Wales, I wondered what average cholesterol levels are like in this part of the world. Imagine my surprise to find that cholesterol levels vary significantly from state to state in Australia and are, in fact, lowest in New South Wales (NSW – the last column in the table below).

Diabegg_2

Source: Carrington M & Stewart S,  2010. Baker IDI Heart & Diabetes Institute, Melbourne, Australia.

So what we are left with is a group of people who are either taking a statin, or who have naturally good cholesterol control, for whom eating 12 eggs a week does not significantly affect their blood lipids.



How many eggs per week?

fried eggBefore I feel comfortable recommending that overweight or obese people with type 2 diabetes can start eating a lot more eggs (whether or not they are on a statin) this study needs to be replicated in a group of volunteers who have naturally poor cholesterol control to see what happens – although I doubt such a study would gain easy ethical approval.

This is such a confusing area relating to type 2 diabetes. What’s more healthy? Eating more or fewer eggs, eating more or less carbohydrates or eating more or less saturated fat? Even national guidelines vary widely.

The Australian National Heart Foundation currently recommends a maximum of 6 eggs per week for healthy people and those with type 2 diabetes; US guidelines recommend that people with type 2 diabetes limit their dietary cholesterol intake to 300 mg/day (one egg contains around 200 mg cholesterol) and no more than 4 eggs per week, while in the UK, there is no suggested limit on the number of eggs consumed and emphasis is placed instead on reducing dietary saturated fats.

Here is my full overview of how to follow a cholesterol-friendly diet. Has your doctor advised you to cut back on eggs? The good news is that runny eggs and toast soldiers are back on the menu, too!

Photo credit: marahwan/bigstock, katherine_lim/flickr


 



About DrSarahBrewer

Dr Sarah Brewer MSc (Nutr Med), MA (Cantab), MB, BChir, RNutr, MBANT qualified from Cambridge University with degrees in Natural Sciences, Medicine and Surgery. After working in general practice, she gained a Master's degree in Nutritional Medicine from the University of Surrey. Sarah is a licensed Medical Doctor, a Registered Nutritionist, a Registered Nutritional Therapist and the award winning author of over 60 popular self-help books. Sarah's other websites are www.MyLowerBloodPressure.com and www.ExpertHealthReviews.com.


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2 thoughts on “How Many Eggs Per Week?

  • Barbara

    Hi, I follow you on Wealthy Affiliate so that’s where I got your website address. I am on a statin which keeps my cholesterol levels within recommended bounds. However my income is officially below the poverty line but I have access to free duck eggs which I know contain higher cholesterol than chicken eggs but free eggs do save me money. I am 75 yrs old and relatively healthy apart from some arthritis. I am overweight with a BMI of approx 30 but not diabetic. Should I be eating these duck eggs or exercising a little more restraint and giving them away instead? regards Barbara Brenchley

    • DrSarahBrewer Post author

      Hi Barbara, That’s an interesting question! Most circulating cholesterol is made in the liver, rather than coming from your diet. As you are on a statin, this will suppress the amount of cholesterol your liver makes. If your doctor has asked you to reduce your dietary intake of cholesterol, you will need to ask him or her the same question as you have asked here. Duck eggs are significantly ‘richer’ than hen eggs so that, per 100g, a duck egg supplies 680mg cholesterol, whereas a hen’s egg supplies 391mg. But, duck eggs are also richer in other beneficial nutrients such as protein (so you feel full and tend to eat less overall), has less saturated fat and more monounsaturates and polyunsaturates, and supplies more of just about every vitamin and mineral, especially vitamin A (carotenes), vitamin D, V6, B12 and folate. Eggs also supply lecithin and choline which have beneficial effects on cholesterol balance. These additional nutrients, in my opinion, more than offset the increased content of cholesterol – especially if you need to save money. Perhaps your doctor would be willing to monitor your cholesterol more regularly as you eat more of the duck eggs to see what effect this has? If you are on a statin, I’d advise taking CoQ10 and vitamin D supplements, too, as explained here:https://drsarahbrewer.com/statins-and-co-enzyme-q10 and https://drsarahbrewer.com/statins-lower-your-vitamin-d-levels but both of these nutrients are present for free in eggs. If you also eat more locally-grown green leaves, vegetables and fruit (eg from farmer’s markets which are relatively cheap) you may find that a more vegetarian-style diet that includes duck eggs improves your cholesterol readings as well as saving money. Do let me know what happens.