I like to hard boil eggs because they are one of very few foods that help when my sugar levels are too low.

But now Im a little paranoid. The other week I read online that if you take an egg out of the refrigerator and shake it, if you can feel stuff moving around inside then its not safe to eat.

I just did that with all 12 eggs I have and according to what I read, they're all bad.

But the usedby date on the carton says 21 August. So, are they safe to eat? How else can I determine if they are safe to eat without cracking the shell and without boiling it first?

  • 3
    Aeron, I would question the original thing you read. were there any references to research?
    – Jennifer S
    Commented Jul 15, 2014 at 19:19
  • I dare to say that you can always feel the yolk moving around if you just shake hard enough... (eggs, which contain hardly any sugar, help against low sugar levels?).
    – SAnderka
    Commented Jul 15, 2014 at 19:21
  • Nah, but I just asked a friend too and he said the same thing but he said it could also be a myth. I cant even find the page I read it on anymore.
    – jay_t55
    Commented Jul 15, 2014 at 19:21
  • @SAnderka I have Hypoglycemia but eggs contain carbs and are oretty high in protein which helps hypo episodes alot (for me, at least). Unless I've been misdiagnosed, again.
    – jay_t55
    Commented Jul 15, 2014 at 19:23
  • @Aeron A large egg contains less than one gram of carbohydrates, so I don't see how it could raise your blood sugar much. A glass of milk, juice, or anything sugary would do so much faster. Perhaps the protein content of eggs has some beneficial effect on your metabolism that smooths out the hypoglycemia, but I seriously doubt it has anything to do with the carb content. Commented Jul 19, 2014 at 0:36

2 Answers 2


I have heard it stated before, but here it is from various sources:

Source 1

Source 2 (confirms the shake test)

Source 3

In general, the air pocket in an egg gets bigger as it gets older due to the permeability of the shell. I think the shake test is a little hinky, unless it actually sounds like water sloshing. I would try the float test; fill a bowl to twice the height of the egg, and place it in. If it sinks to its side, it's fresh. If it stands on its end, it's probably good, but needs to be used quickly. If it floats, toss it.

  • 3
    None of those sources are authoritative. They're all just repeating the same test for telling whether an egg has passed some arbitrary point of freshness - if it fails, it means it's not fresh, not that it's not safe.
    – Cascabel
    Commented Sep 15, 2014 at 20:15
  • @Jefromi that's the best you are likely to get. The only other info I can find online is that the USDA recommends you not keep refrigerated eggs longer than five weeks. I gave the best answer available with the best information you can find on google. If an egg is of questionable freshness, it should be tossed. The question specifically asked if they are safe to eat, and being 'arbitrarily fresh' implies that they probably are.
    – JSM
    Commented Sep 15, 2014 at 21:29
  • 1
    It's not quite that simple. It's possible to get eggs that fail this test but are still before the expiration date - they've just dried out quickly. Those eggs are still safe.
    – Cascabel
    Commented Sep 15, 2014 at 21:35
  • 2
    Given that I raised chickens for a couple of decades, here's my take on it: if you try to float an egg and it touches bottom at all, it's safe. If it doesn't touch bottom, even if it only barely breaks the surface, I'd throw it out. You might end up turfing out an occasional safe one, but chances are good that it would not have been the best tasting (or smelling) egg anyway.
    – Shalryn
    Commented May 18, 2017 at 22:31

It means they are not extra fresh, so they have to be cooked long enough. Raw or soft-boiled eggs need to be extra fresh, but hard-boiling them is just fine if they are not !

When an egg gets old (only a few days old actually), the white part tends to loosen itself (you can break a fresh egg and an old egg and see for yourself), so the yellow part can move more freely ; that's why you can feel it when you shake it.

  • 3
    Why do raw or soft-boiled eggs need to be extra fresh? As long as eggs have been stored properly and aren't spoiled, I would feel comfortable cooking them by any method. Commented Jul 19, 2014 at 0:40
  • In general, the more old eggs are, the more they have to be cooked. The risk of salmonella and other bacteria gets higher when the egg gets older, and the only way to get rid of these potential bacteria is to cook the egg completely.
    – nathou
    Commented Jul 19, 2014 at 11:55
  • Storing them properly can slow down the process, but if bacteria are present they will spread eventually.
    – nathou
    Commented Jul 19, 2014 at 12:01
  • 2
    If bacteria such as salmonella have grown to the point that the egg is dangerous, then no amount of cooking will make it safe because cooking does not destroy the toxins they produce. You'd need to show me a citation if you believe otherwise. Commented Jul 19, 2014 at 16:33
  • 1
    "Thorough cooking kills the bacteria" : cbc.ca/news/technology/salmonella-faqs-1.774707. The FDA also advises to cook thoroughly to kill the bacteria (in addition to proper handling and storing of course) and seems to say that eggs are safe this way : fda.gov/food/resourcesforyou/Consumers/ucm077342.htm. Seems like the toxins they produce are not enough to make you sick.
    – nathou
    Commented Jul 20, 2014 at 16:51

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