Brief Answer:
It can be a indicator of cardiac problem!

Detailed Answer:
Hi ,
Firstly thanks for choosing health care magic for your query!

Have seen all your reports most of them are perfectly normal,though serum lipase is a bit derange yet it has nothing to do with lightheadedness.
Lightheadedness while climbing upstairs can be because of-
1)Coronary artery disease-If there is a blockage in coronary arteries supplying the heart the pumping functions are affected , hence heart will maintain blood supply when body needs are minimal,But while climbing upstairs as the demand increases ,it cant be met hence person can feel light headed.

i would suggest you to go for -
2d ECHO- to rule out motion abnormalities in wall of heart and to know if ejection fraction is normal.
Tread mill test-An exercise stress test is primarily used to help to determine if your heart receives enough oxygen and proper blood flow when it needs it most, such as when you are exercising.
2d echo and Tmt taken together have a sensitivity of more then 85% to rule out CAD.

A carotid doppler -A carotid Doppler is an imaging test that uses ultrasound to examine the carotid arteries located in the neck. This test can show narrowing or possible blockages due to plaque buildup in the arteries due to coronary artery disease.Carotid artery supplies blood to brain ,blockage in it can cause symptoms like dizziness,fatigue,presyncope.

Now answer to your question,
Zincovit is a multivitamin anioxidant capsule - works by producing and maturing the red blood cells; treating vitamin B12 deficiency; increasing absorption of calcium and phosphorus required for strong bones.Though its a general body tonic ,yet lightheadeness on exertion with weekness could be some thing more then just vitamin defieciecy.

Advice
Start Zincovit
And get all tests done at a standard lab,
Follow up with reports!
In case you have any other query feel Free to ask!

Thanks,

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