The Things Which Breaks your Ramadan Fast and Which Does Not.

What does not break your fast

Fasting in the way of the muslims is not an easy deal and while you are doing it, you  must make sure that you are doing it properly. Sure, you might think that not eating and drinking throughout the day keeps your fast intact, but that’s totally wrong. In fact, there are a whole lot of other things that might break your fast and you need to be aware of:

The things that break or Reduce the Effect of your fast and the Things that do Not break your Fast.

1. Injections:

What Breaks your Fast: It is not mandatory for you to fast if you are sick, but your fast will be counted if you keep it; however,  if you have to take injections which carry constituents of nutritional value such as saline, your fast will break.
What Does Not Break your Fast: You are allowed to have the injection if it is a tranquiliser or an analgesic for pain pr that which is similar to it then this does not break the fast. Shaykh Ibn Jibreen / (Fataawa Ramadan, Volume 2/ Page 485/ Fatwa No. 433)

2. Vomiting:

What Breaks your Fast: Intentional vomiting of any kind will immediately render your fast useless.
What Does Not Break your Fast: Unintentional vomiting will not break your fast. Reference: (Fataawa Ramadan, Volume 2/ Page 481/ Fatwa No. 424)

3. Bleeding:(Excluding Menstrual Bleeding)

What you need to remember is that bleeding wont break your fast, but sucking on it will.
What Breaks your Fast: There is a strong disagreement about this in the Muslim world; however, the general consensus is that if blood other than menstrual blood is sucked during the time of fasting, the fast will break. So, if you cut your finger and suck the blood after cutting it, your fast will break.
What Does not Break Your Fast: Not sucking on the blood after you experience a cut will not break your fast. Reference: Shaykh Ibn Baaz / (Fataawa Ramadan, Volume 2/ Page 476/ Fatwa No. 416)

4. Donating Blood During Fasting

Under any circumstances, if you are donating blood during the time of fasting, your fast will break. Reference:Shaykh Ibn Fowzaan / (Fataawa Ramadan, Volume 2/ Page 467, Fatwa No.405) 

5. Drawing Blood out for the purpose of Analysis

Your fasting will not be violated and it will remain intact if you are drawing a small amount of blood for the purpose of blood test. Reference: Shaykh Ibn Baaz (Fataawa Ramadan, Volume 2/ Page 465/ Fatwa No.400) 

6. Semen

What Breaks your Fast: Intentional or unintentional ejaculation of semen whilst one is with his wife will nullify his Ramadan fast completely.
What Does Not Break your Fast: Wet dreams, meaning if you ejaculate during your sleep due to an arousing dream, your fast will not break as long as you have a purifying bath after waking up. Reference:Shaykh Ibn Fowzaan / (Fataawa Ramadan, Volume 2/Page 440/Fatwa No.365), also (al-Muntaqaa min Fataawa ash-Shaykh Saalih ibn Fowzaan, Volume 3/ Page 162)

7. Love and Affection

What breaks your fast: Kissing or showing intimate affection to any person of the opposite sex who does not fall in your immediate family or your wife, yes and that includes your boyfriends and girlfriends as well, will nullify your Ramadan fast. So,  forget about kissing your bfs and gfs during fasting, okay bro/sis?
What Does Not Break your Fast: Kissing or showing intimate affection to your wife is permissible during fasting as long as you do not engage in sexual intercourse or ejaculate.

Reference: Shaykh Ibn al-‘Uthaymeen / (Fataawa Ramadan, Volume 2/Page 454/Fatwa No.383) 

8. Breastfeeding Mothers

Mothers who are breastfeeding their children during fasting will have their fasts nullified and wont be granted.

Reference: The Permanent Committee for Islaamic Research and Fataawa, comprising – Head: Shaykh ‘Abdul-‘Azeez ibn ‘Abdullaah ibn Baaz; Deputy Head: Shaykh ‘Abdur-Razzaaq ‘Afeefee; Member: Shaykh ‘Abdullaah ibn Ghudayyaan. (Fataawa Ramadan, Volume 2/ Page 470/ Fatwa No.408), also (Fataawa al-Lajnah ad-Daa.imah lil-Buhooth al-‘Ilmiyyah wal-Iftaa., Fatwa No.11917) 

9. Tasting Food During Cooking

What breaks your fast: If the food goes in through your throat at the time of fasting, your fasting will be nullified or have it’s effects reduced depending on whether you did it intentionally or unintentionally.
What does not break your fast: If you put it on the tip of your tongue making sure that none of it reaches your throat. Reference:haykh Ibn Jibreen / Fataawa Ramadan, Volume 2/Page 543/Fatwa No.524) / (Fataawa as-Siyaam libni Jibreen, Page 46)

10. Brushing During Fasting

As long as you make sure that nothing goes through your throat and do not gurgle exaggeratedly afterwards, your fast will remain intact. However, according to Muslim scriptures, you are advised to use meswak to brush during the time of Ramadan.
Reference:Fataawa Ramadan, Volume 2/ Page 496/ Fatwa No. 445), also (al-Muntaqaa min Fatawaa ash-Shaykh Saalih ibn Fowzaan, Volume 3/ Fatwa No. 158.

11. The Use of Bad speech During the Month of Ramadan

It’s a common misconception that using bad words during the month of Ramadan only lightens your fast, but that’s wrong, If we read the saying of Allaah (subhaanahu wa-ta’aala), {O you who believe! Fasting is prescribed for you as it was prescribed for those before you, that you may become al-Muttaqoon (the pious)} [Soorah al-Baqarah, Aayah 183], we find the wisdom behind the obligation to fast is attaining fear of Allaah (Taqwah) and worshipping Allaah. Taqwah is to abandon all that is haraam and incorporating all that is commanded, avoiding all that is warned against. The Prophet (sal-Allaahu ‘alayhe wa-sallaam) said: ((One who does not abandon evil talk and actions, then Allaah is not in need of him abandoning his food and drink (i.e. his fasting)). And so, the acts of backbiting, lie, slander or trade in a haraam manner will reduce the effects of your fast and the repetitive use of it may completely nullify the rewards of your fast.

12. Listening to Music or watching Movies at the time of Fasting:

Although it does not nullify your fast, there are many evidences found in Muslim scriptures which might render that doing these sort of activities may reduce the rewards of the fast.