The advertising regulator received five complaints that an advert from the aid agency broadcast on the Boomerang and Cartoon Network channels was distressing for young children.
The voice-over for the advert asked "Who cares about children on the very edge of survival?" and showed close-ups of the faces of three children who looked ill or severely malnourished. It asked viewers to give £2 a month to the appeal.
In a ruling published today, the regulator rejected the complaints because the advertising watchdog Clearcast had seen the advert before it was broadcast and had imposed restrictions on when it could screened.
After several stations queried the suitability of the advert, Clearcast subsequently warned broadcasters it contained "distressing scenes" and advised them to view it to determine its acceptability for screening during programmes aimed at children under nine.
The ASA ruling said the images were about serious issues and showed children in distress, but "the ad did not use shocking claims or images merely to attract attention; it made clear the issue was serious but that action could be taken to prevent it".
Although the advert was upsetting it was "unlikely to harm young viewers even if watching alone", the ASA said. It concluded it was acceptable for it to be shown on dedicated children's channels.
Tracy Horner, head of direct marketing at Care International UK, said the charity gave careful thought to where the advert should be shown and it had generated a positive response.
"Many other overseas development charities with similar adverts already advertised on Cartoon Network and Boomerang," she said. "We constantly have to weigh up our duty to our beneficiaries of raising funds as cost-effectively as possible against the possibility that we might offend some people."