How long should dietary supplements be taken after opening them?

There is actually no universal standard answer to this question. Most conventional dietary supplements are recommended to be consumed within 3 to 6 months after opening. The specific disposal time cannot be copied from the shelf life of the unopened bottle. It must be judged based on the category, storage conditions, and changes in the properties of the supplement itself.

A while ago, I helped my mother pack the family medicine box and came across a typical counterexample. Her bottle of ordinary vitamin C had been open for almost 11 months, and the shelf life printed on the bottle was still one year short. The pills had oxidized from pure white to light lemon yellow, and she was reluctant to throw them away. She said that she had to twist the cap every time. It was very tight, so it must not be broken. I dragged her and asked the nutrition nurse, who said that this oxidized vitamin C has long been inactive. It is like chewing sugar tablets, so it is useless. If the deterioration is serious, it may cause stomach upset, so I finally persuaded her to throw it away.

There is actually a lot of controversy in the health care circle about the expiration date after opening. There is an old school of users who think that as long as the shelf life on the package has not reached the expiration date, there is no hair, and there is no odor, they can eat it. There is also a group of people who are particularly honest about the ingredients. They say that as long as the package is opened, no matter what category it is, it must be thrown away at most 3 months, even if it is less than a day. In fact, both opinions are too absolute, and there is no such a one-size-fits-all truth.

If you buy multivitamins and lutein tablets that are individually sealed with aluminum foil, as long as the individual tablets are not broken or bulged, even if the big box has been unpacked for more than half a year, you will still have no problem eating the shelf life on the package. The eye protection tablets I prepared before were individually packaged and took almost 9 months to consume. The color and hardness of the last few tablets are no different from the first one. I checked the relevant testing data and found that the oxidation rate of the active ingredients in this independent packaging is less than 1%, which does not affect the effect at all. But if the whole bottle of powdered supplements, such as protein powder and iron powder, is very easy to absorb moisture, even if you tighten the cap every time, it may clump after two months during the rainy season in the south, let alone half a year. I bought a can of collagen peptide last year, but I forgot to put it in the drying box during the rainy season. It only took 2 and a half months after opening and it became sticky and clumped, so I had to throw it away.

Supplements such as probiotics and live fungi are inherently weak in activity. If they are not refrigerated according to the instructions after opening, they may be almost inactive within a week. Even if they don't look bad, eating them is almost like eating them in vain. There are also fish oil and DHA that contain a lot of fat. If it smells bad after opening, it means the fat has gone rancid. Regardless of how long it has been opened, you have to throw it away even if it has just been opened for a week. Eating it will put a burden on the body.

In fact, there is really no need to memorize the time point of 3 months and 6 months. It is much more reliable to check the characteristics before taking each time than to check the time. If the tablets are discolored, have spots, or stick to flakes, the capsules are sticky or cracked, or the powder is clumped and has a strange smell, just throw it away without hesitation. After all, we buy supplements to supplement nutrition, and we cannot save money by eating useless ones for half a day.