Thank you for your question.
The burning in your feet could be a parathesia related to being overweight. Of course, the arthritis in your knees also will be related to your weight.
To be sure about your burning in your feet, be sure to see your primary doctor and consider seeing a podiatrist.
You should be considering your overall health and try to find ways to lower your weight.
Be sure to have your doctor check your thyroid function including your TSH (thyroid stimulating hormone), total and free T4, and total and free T3, and anti-TPO antibodies.
Also, make sure that you are properly hydrated. I can not emphasize the importance of water enough in helping with both weight loss and the pain associated with arthritis. Check out the book "Your Body's Many Cries for Water."
Here is some basic advice regarding weight loss.
1. You need to decide what you are wanting in terms of your health. "Decide" means to cut off from all other possibililty, and you need to realize this if you are going to reach your health goals. Create the image in your mind of what you want, with a reasonable expectation, and hold on to that image. You must tell yourself on a daily basis that you can do it. Understand that health is a journey and not a destination. Health is an ongoing process and a way of life. Now is the time for you to get what you want, so "decide" now.
2. Diet: Simply, avoid carbohydrates. If you followed this one rule alone, you would find your way towards achieving the goals you are looking for. This means avoid pasta, bread, grains, any kind of processed carbohydrate, etc. You can eat all the vegetables and fruits you want, just keep the ratio of vegetables to fruit, 2:1. Eat all the good fats you want, and focus on lean protein sources such as fish, poultry, lean meat, etc. The carbohydrates are causing insulin resistance in a large portion of the western population. Also, avoid the 5 top allergen causing foods, soy, peanuts, corn, dairy (keep this to a minimum), wheat (if you avoid carbs in general, you will inevitably stay away from wheat). Allergen foods, when consumed, make it harder to lose weight.
3. Increase your metabolism. Eat smaller frequent meals. Look into adding coconut oil to your diet. Drink green tea.
4. DRINK PLENTY OF WATER! You should consume 1/2 your body weight in ounces daily, then add 6 more ounces of water for every 8 ounces of caffeine or alcohol you consume. I can not stress the importance of drinking plenty of water to encourgae weight loss
5. Exercise! Depending on your physical fitness, you should start off slow and then increase both the intensity and the frequency of your exercise.
Finally, consider seeing a naturopathic medical doctor by going to www.naturuopathic.org to find a doctor in your area.
In the end, there is no magic bullet. It will take dedication, committment, and a little know how.
I hope this helps.