It’s right there, at the top of the American Red Cross website.

“The need is constant, the gratification is instant. Give blood.”

“The need” is unequivocal, and has been for decades. You may hear about particularly urgent shortages periodically — the demand is currently so acute that some blood banks and bloodmobiles are giving gift certificates to donors — but collection groups never grapple with a glut of donations.

“The blood supply is like a cell phone battery, it constantly needs recharging,” said Maya Franklin of the Carolinas Blood Services Region. “We sincerely appreciate those who have responded to the call to help save lives and encourage those who haven’t to consider rolling up a sleeve and give the gift of life. It only takes about an hour but can mean a lifetime for patients.”

Nearly 61,000 fewer blood donations than needed were given through the Red Cross in May and June, prompting the emergency call for donations in early July. The shortfall was the equivalent of the Red Cross not receiving any blood donations for more than four days.

So while it’s great to respond to the call to action when the reserves run dry, it’s better to give as often as you can. Make it a habit, as it were. You can even download an app (of course) to help with reminders every time you are eligible, which is every 56 days for whole blood donations.

As a special thank you, those who come out to give blood or platelets with the Red Cross through Aug. 31 will be emailed a $5 Target eGiftCard.

The excuses for not donating run the gamut; some are more legitimate than others, none should be voiced before you’ve tried.

Yes, you may be ineligible because of anything from low iron content to a recent overseas trip. Yes, a fear of needles can make it harder, and you can almost certainly find someone with a mini-horror story of a swollen arm from a misdirected insertion. Yes, the screening process has gotten much more involved than decades ago, as any long-time donor will attest.

But giving blood is overwhelmingly safe, almost always involves little more than a brief sting from the needle, and can even be relaxing — after all, you get to lie down for about 10 minutes when donating whole blood. The whole process can take as much time as some people spend on lunch.

And it is quite literally life-saving. One donation can help up to three people because it is processed into several components that can fulfill different needs of different people.

But most importantly, it is essential. We may have flown to the moon and mapped the human genome, but science has yet to manufacture a replacement for what courses through our veins.

There is no substitute for blood.