In Ayurveda there are mainly three dosha Vata , Pitta & Kapha . And sapta dhatu – Rasa , Rakta ,mamsa , Meda , Asthi ,Majja & Shukra .

When Meda dhatu (Fat) increases excessively. Weight increases and it can be seen on body parts like abdomen , sides of abdomen, neck , buttocks etc.

What are the reasons of weight gain according to Ayurveda

A. Aharatmaka Nidana – Diet factor

Due to continuous consumption of Kapha Vardhak Aahara, Meda Dhatu is being increased by principle of Samanyam Vriddhi Karanam.

Ati-Guru sevan
due to its guru paki and sheeta veerya property test time to digest and increases the kapha dosha which affects the dushya meda.

Madhura ati sevana
Very heavy and have sheeta, guru, snigdha and parthivapya property and increase the madhurasa of kapha after digestion.

Sheetahara sevana
It has guru, mridu, sthula, pichhhila, snigdha, manda, sthir and shlakshana qualities which increase the styanavta of kapha dosha. It produces the obstruction in channels.

Ati-Snigdha,Shleshma bahula,and Pichhila Aahara
These type of aahara has guru, sheeta, sthula, pichhil properties they affects the meda dhatu by increasing kapha doshas in quantam.

Ati Bhojan
Taking excessive amount of food It will affect the pachakagni leading to delayed or improper digestion. As a result of this, ama rasa is produced to which spreads all over the body like a toxin. It causes obstruction in medovaha strotas and produces medorog.

Ati Pishtanna sevan
They are difficult to digest and aggravate the kapha dosha and produce ama by affecting the pachakagni.

Navanna sevan,
Navanna is abhishyandi in nature and produces strotorodha by aggravating the kapha dosha, ultimately increase in meda dhatu which result into medorog.

Anupa Mamsa Sevan
Consumtion of excessive anupa mamsa aggravates the kapha dosha and vitiates the medovaha strotas causing medodhatwati sanchaya, which leads to medorog.

B. Viharatmaka nidan:

Vyavaya (lack of sexual intercourse)
Increases the shukra dhatu and produces the shrotorodha, which leads in increase of meda dhatu.

Vyayama (lack of exercise)
Increases the meda dhatu and (happy and comfortable living without any work) – It leads to kapha vriddhi and affects the meda dhatu which produces medorog.

Diwaswapna (Day sleep)
Diwaswapna increase the kapha and affects the meda dhatu by obstructing the channels, which later on leads to the production medorog.