3 added more explanations and a more direct answer to the claim.
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You may survive for longer than two months without eating.

Khader Adnan for example

A father to two daughters, Maali and Bissan, Randa was pregnant with their third child, when he was arrested by the Israeli Army on 17 December 2011 from their home in Arraba in the middle of the night. The next day he began a hunger strike that ended 66 days later on 21 February 2012.

And thanks to the Igloo effect (and warm clothing and sleeping bag), it's not so strange that he may have survived, provided he had enough water.

Snow is used because the air pockets trapped in it make it an insulator. On the outside, temperatures may be as low as −45 °C (−49 °F), but on the inside the temperature may range from −7 °C (19 °F) to 16 °C (61 °F) when warmed by body heat alone.

I would add that some doctors are forwarding a kind of hibernation theory regarding survival in low temperatures, as in the case of Mitsutaka Uchikoshi

Injured hiker survived 24 days on mountain by 'hibernating'

A Japanese civil servant has described for the first time how he survived for more than three weeks in a mountain forest without food or water in what doctors believe is the first known case of a human going into hibernation.

regarding this case in particular the claim that he survived for two months on snow alone is somewhat contested.

Swedish man was not trapped in his car

"It wasn't snowed in. Not the right passenger door," said Andreas Gidlund, one of the two traffic policemen who pulled Mr Skyllberg's emaciated body from the vehicle. "If you look at the back door, on the left side, it was very compacted snow – but on the right side, it was very loose snow. "So I imagine that is the place where he had been going out. There wasn't as much snow there as there was on the other side. It had been opened every now and then." But other people involved in the initial rescue maintain that he was indeed trapped – and that his miraculous story of survival is, as initially seemed, astounding but true.

...

"I think he was trapped," said Erik Ostman, one of the firemen who brought Mr Skyllberg from the car in a tank-tracked off-road vehicle. "When we arrived, there had only been two scooters who'd driven there, so the road was pretty untouched. The snow was maybe 70cm deep."

Anyway, there were numerous food and drink wrappers in the car when he was found, so maybe he had food for some time at least

what to do when snow traps you in a car - pictures

You may survive for longer than two months without eating.

Khader Adnan for example

A father to two daughters, Maali and Bissan, Randa was pregnant with their third child, when he was arrested by the Israeli Army on 17 December 2011 from their home in Arraba in the middle of the night. The next day he began a hunger strike that ended 66 days later on 21 February 2012.

And thanks to the Igloo effect (and warm clothing and sleeping bag), it's not so strange that he may have survived, provided he had enough water.

Snow is used because the air pockets trapped in it make it an insulator. On the outside, temperatures may be as low as −45 °C (−49 °F), but on the inside the temperature may range from −7 °C (19 °F) to 16 °C (61 °F) when warmed by body heat alone.

You may survive for longer than two months without eating.

Khader Adnan for example

A father to two daughters, Maali and Bissan, Randa was pregnant with their third child, when he was arrested by the Israeli Army on 17 December 2011 from their home in Arraba in the middle of the night. The next day he began a hunger strike that ended 66 days later on 21 February 2012.

And thanks to the Igloo effect (and warm clothing and sleeping bag), it's not so strange that he may have survived, provided he had enough water.

Snow is used because the air pockets trapped in it make it an insulator. On the outside, temperatures may be as low as −45 °C (−49 °F), but on the inside the temperature may range from −7 °C (19 °F) to 16 °C (61 °F) when warmed by body heat alone.

I would add that some doctors are forwarding a kind of hibernation theory regarding survival in low temperatures, as in the case of Mitsutaka Uchikoshi

Injured hiker survived 24 days on mountain by 'hibernating'

A Japanese civil servant has described for the first time how he survived for more than three weeks in a mountain forest without food or water in what doctors believe is the first known case of a human going into hibernation.

regarding this case in particular the claim that he survived for two months on snow alone is somewhat contested.

Swedish man was not trapped in his car

"It wasn't snowed in. Not the right passenger door," said Andreas Gidlund, one of the two traffic policemen who pulled Mr Skyllberg's emaciated body from the vehicle. "If you look at the back door, on the left side, it was very compacted snow – but on the right side, it was very loose snow. "So I imagine that is the place where he had been going out. There wasn't as much snow there as there was on the other side. It had been opened every now and then." But other people involved in the initial rescue maintain that he was indeed trapped – and that his miraculous story of survival is, as initially seemed, astounding but true.

...

"I think he was trapped," said Erik Ostman, one of the firemen who brought Mr Skyllberg from the car in a tank-tracked off-road vehicle. "When we arrived, there had only been two scooters who'd driven there, so the road was pretty untouched. The snow was maybe 70cm deep."

Anyway, there were numerous food and drink wrappers in the car when he was found, so maybe he had food for some time at least

what to do when snow traps you in a car - pictures

2 added 570 characters in body
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You may survive for longer than two months without eating.

Khader Adnan for example

A father to two daughters, Maali and Bissan, Randa was pregnant with their third child, when he was arrested by the Israeli Army on 17 December 2011 from their home in Arraba in the middle of the night. The next day he began a hunger strike that ended 66 days later on 21 February 2012.

And thanks to the Igloo effect (and warm clothing and sleeping bag), it's not so strange that he may have survived, provided he had enough water.

Snow is used because the air pockets trapped in it make it an insulator. On the outside, temperatures may be as low as −45 °C (−49 °F), but on the inside the temperature may range from −7 °C (19 °F) to 16 °C (61 °F) when warmed by body heat alone.

You may survive for longer than two months without eating.

Khader Adnan for example

And thanks to the Igloo effect (and warm clothing and sleeping bag), it's not so strange that he may have survived, provided he had enough water.

You may survive for longer than two months without eating.

Khader Adnan for example

A father to two daughters, Maali and Bissan, Randa was pregnant with their third child, when he was arrested by the Israeli Army on 17 December 2011 from their home in Arraba in the middle of the night. The next day he began a hunger strike that ended 66 days later on 21 February 2012.

And thanks to the Igloo effect (and warm clothing and sleeping bag), it's not so strange that he may have survived, provided he had enough water.

Snow is used because the air pockets trapped in it make it an insulator. On the outside, temperatures may be as low as −45 °C (−49 °F), but on the inside the temperature may range from −7 °C (19 °F) to 16 °C (61 °F) when warmed by body heat alone.

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You may survive for longer than two months without eating.

Khader Adnan for example

And thanks to the Igloo effect (and warm clothing and sleeping bag), it's not so strange that he may have survived, provided he had enough water.