21 Interesting facts about veins

Veins hold up to 70% of the entire blood and are very distensible. They can endure huge changes in volume, resulting from a haemorrhage or transfusion. Tweet This

Some veins can constrict in response to nerve stimulation.  Tweet This

Blood samples are normally taken from veins, having thinner walls, larger diameters and lower blood pressure compared to arteries. Tweet This

Larger veins possess one-way valves ensuring that blood travels in the correct direction and preventing the development of undue back pressure. Tweet This

YOU MAY ALSO CHECK OUT: 19 FACTS ABOUT THE HUMAN VEINS

Sometimes valves cease to function, causing veins to distend permanently, with blood flowing backwards and collecting in the vein. Tweet This

Swollen and enlarged veins are called varicose – usually blue or dark purple. In appearance, they may be twisted, lumpy or bulging. Tweet This

Varicose veins are usually due to weak vein walls and valves. In rare cases, causes may be: previous blood clot, swelling or tumour in the pelvis, abnormal blood vessels. Tweet This

Varicose veins’ symptoms include pains, dry skin and colour changes in the lower leg, heavy legs, swollen feet and ankles or muscle cramps. Tweet This

Varicose veins are a common condition, affecting up to 35% of adults. Tweet This

The first recorded case of varicose veins dates back in 86 BC, when the Roman general Caius Marius described his suffering. Tweet This

Giraffes have the greatest pressure in their legs amongst all animals. Yet, they never get varicose veins because of their extremely thick skin. Tweet This

Up to 75% of men are affected by varicocoele, which is a vein enlargement that occurs in the left testicle and cause discomfort. Tweet This

Any vein can become varicose, but as standing and walking put extra pressure on the lower body, they most frequently develop in the calves. Tweet This

Trunk varicose veins are near the skin surface and are thick and knobbly; they are visible and often very long. Tweet This

Reticular varicose veins are red and are sometimes grouped together into a network. Tweet This

Telangiectasia varicose veins, a.k.a. thread veins or spider veins are small clusters of blue or red veins that can appear on your face or legs. Tweet This

Women are more likely to be affected by varicose veins than men because female hormones tend to relax the walls and valves of veins. Tweet This

Risk increases if a close family member has varicose veins. Tweet This

As you get older, your veins start to lose their elasticity and valves inside them become less efficient. Tweet This

Being overweight puts extra pressure on your veins and valves, as they have to work harder to send the blood back to your heart. Tweet This

The impact of body weight on the development of varicose veins is thought to be more significant in women. Tweet This