Brief Answer:
in most persons blood has to be ruled out first

Detailed Answer:
HI, thanks for using healthcare magic

Red discolouration in or on the stool can either be related to foods or medication used or due to blood within the stool.

Certain foods can cause a slight red addition in colour to stool, foods such as tomatoes, tomato juice, beets, food with a red colouring, red wine.

Medication such as iron supplements can also cause abnormal appearance to the stool.

In terms of blood, this can occur in as a result of: (1) inflammation of the colon (colitis),
(2)bleeding due to medication (NSAIDS, warfarin),
(3)trauma to the colon,
(4)masses in the colon (non cancerous or cancerous lesions can cause bleeding)
(5)infections of the colon
(6)hemorrhoids- there is usually a previous history of problems with hemorrhoids and constipaiton
(7)anal fissures- these would normally be very painful
(8)diverticular disease- this condition is common as persons age. It is related to outpockets developing in the colon
(9)ulcers in the stomach- history of pain in the early morning or at night, burning discomfort in the abdomen

You should consider having your doctor send a stool sample to check for blood. This is normally done on at least 2 samples, in some cases 3, to make sure none is present.This is a test called fecal occult blood, this can identify blood that cannot be seen by the naked eye

If blood is identified then further testing, usually imaging tests would be required.

I hope this helps, feel free to ask any additional questions

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Brief Answer:
It can cause the red spot

Detailed Answer:
Hi

Yes , tomato sauce ,plain tomatoes or juice can cause a red discolouration.

Since you had negative screening investigations recently then blood is not likely.

You can consider monitoring for any recurrence

Please feel free to ask anything else

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