"Why is there starvation/poverty in sub Saharan Africa" 
There are many reasons. But the two biggest ones. I believe, are drought and IMF/World Bank imposed free market/free trade "reforms." Since the late 70s, Sub Saharan African countries have been forced to adopt free-market and free-trade policies through conditions imposed on it by so called Structural adjustment Programs. Institutions like the IMF and World Bank and others encourage the rich and powerful Sub Saharan Africa and other poor countries to take on mountains of debt. The risky loans yield high returns, and when the system crashes, structural adjustment programs transfer the costs to the poor, who never borrowed the money to begin with, and gained little from it. The IMF routinely works with finance ministers of impoverished countries to set budget ceilings on things like health, education, water, sanitation, agricultural infrastructure, etc, in full knowledge that the consequences could be mass suffering and death, which they try to offset with aid money. But when the aid money isn't enough, it results in a human catastrophe with deaths from hunger, disease, and unsafe water on the scale of world war. 

"Are they under capitalism or socialism?" 
Again, most African countries have had free market and free trade reforms imposed on them by institutions like the IMF, World Bank, and GATT, much to the continents detriment. Capitalist exploitation, with its monopolies and cartels, are the enemy of the underdeveloped world. There's a better choice of a socialist system, a system devoted to the people, based on the belief that man is the most precious asset. It will allow them to progress faster, ruling out the possibility of a caricature society where a privileged few hold the reigns of political and economic power. 

"What can be done to change sub saharan africa into a true democracy?" 
There will have to be a multi-level system of democratic governance. People in those countries will have to organize to raise their standard of living. Democracy means far more than simply periodic elections. It requires empowering collective action, and eliminating the hold of unaccountable global institutions like the World Bank and IMF on Sub Saharan Africa's economies. It means creating vehicles through which people can act in their common interests. For example, in Mali, a cooperative formed by a group of women in the 70s in the small town of Markala became the nucleus for a woman and development program that spread to more than 30 village groups. The women conduct such income generating activities as soap-making, small animal raising, cloth dying, and raising vegetables. They also receive training in how to manage the c👎ops. Such programs give ordinary people to control and benefit from local economic activity.
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Solve poverty in your own country first. 

Stop helping Africa, Africa is not asking for your help. 

You are cluless about what you are talking about. 
Sorry to break it down to you. No, you are not helping Africa. You are just trying to boost your low self esteem so that you can feel your life worthy. Get some education and know that you are absolutely not helping Africa but sending some food and clothes or what have you to solve malaria. If you were educated enough, I would call you hypocritcal, but you are not. If you really want to help Africa, you should buy what africans produce. That's the only way people can pull themselves up. It grinds my gear to constantly hear westerners cry all the time how badly they want to help Africa, but yet, they dont mind putting all the trade barriers to african products. Africa will be better off without you, keep your dollar/euro in your country and let us breath and build our continent. But, no you cant. As always, you have to create a mess everywhere on this planet. 

If you really want to help Africa, you should be talking to your government to stop intervening in African affairs, sending mercenaries to Africa to create chaos and profit from it. 
If you really want to help Africa, you should stop consuming the propaganda about how poor Africa is or how people live in a slum there. The images you are referring to, I can go to your country and recreate exaclty the same thing or even worst to show a bad image of your people. 

Anyway, I can go on forever why should not send a penny to Africa because you have seen a video about poor people. These videos are made for one purpose: to boost your self esteem so that you can fel better about your life. And apparently, the videos are doing a wonderful job. 
Do you want to get educated about Africa? Pay a visit, or watch the african channel on cable tv or online, talk to real africans. Stop consumming the hatred perpetrated by the media. 

Addtionnal info: look, I did not have to spend that much time to find example of people who need help just here in USA. CNN is reporting that 1.5 million children are homeless here. Instead of crying how you want to help people in Africa, why dont you go and help this little american blond? http://www.cnn.com/2009/US/03/10/homeless.children/index.html" rel="nofollow" data-rapid_p="11" style="color: rgb(44, 70, 199); text-decoration: none; font-family: 'Helvetica Neue', Helvetica, Arial, san-serif; font-size: 13px; line-height: 16.25px;">http://www.cnn.com/2009/US/03/10/homeles... ? 

No, you wont because that does not give you the same fulfillment, the same sense of ego boosting mantra. 

You would rather go around and spread the idea of a dying, helpless Africa without realizing how bad your attitude affects the revival of the continent's economy. Enough, is enough!
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The major reason I can cite for poverty in Sub Saharan Africa is bad leadership in form you of greed.

Africa is really blessed with all sorts of resources but our leaders are too greedy , thinking of themselves and mismanaging what we have to better the lot of the citizens in African countries.


Even western countries know how blessed Africa is and they exploit us because our leaders are so greedy.
**I love being me.**