An egg a day is not harmful

The concern about egg is due to its cholesterol content.One egg contains 300 mg of cholesterol. But heart disease is more likely to occur with saturated fats (butter),and trans fats, rather than cholesterol intake.

It is better to eat an egg rather than carbohydrate rich foods(poha, upma,pav bhaji). It will raise HDL cholesterol and decrease blood glucose.

However diabetics have more risk of heart disease with egg . Hence they should limit their egg intake.

This is about the adults. But children need good amount of proteins and egg is the best. Animal proteins are called First Class proteins because they have all the essential amino acids.
The quality or the biological value of protein from all food (animal and plant foods) has been studied:

Protein                      Biological value

Breast milk                    100
Egg                               100
Cow milk                        90
Fish                                80
Meat                               74

Rice                                80
Soybean                         78
Wheat                             66
Bengal gram(chole)        74
Groundnut                      55
Maize                              50


Why egg?

High biological value of protein

Low calories (70 calories per egg)

Cost effective

Meets the nutrient needs of children

High omega -3 contents

Cholesterol is not an issue in children


Nature's hygienic pack

But in our culture egg is not easily accepted. Many communities in India strictly avoid egg. If we tell them that egg has highest biological value, they are not impressed and not convinced with this scientific information.

There are many who avoid egg on certain days. "Today is thursday, hence I will not egg." If there was any logic behind this, we could have argued with that person. But this is beyond logic and hence we cannot convince that person.

I only advice these persons that they should not refuse the egg to their children,even on monday or thursday. Let them grow in a healthy way, especially the girls. Indian girls are under nourished and have low body weight. They are going to marry and get pregnant one day. Hence they should have normal body weight before they marry.  
  
But unfortunately Indian girls also have inhibition about egg.
This is partly due to the upbringing and religious atmosphere at home.
They need nutritional counseling.