Whenever you begin a diet and exercise routine, the following two things are almost always recommended for muscle growth: increased protein and fatty acids.
I am a skeptic, and I believe we all ought to be more critical of psuedoscience fads in this Internet age. So, let’s consider the following questions:
“You gotta eat more protein, brah,” says the over-muscled guy in the bodybuilder tank top as he tosses you a giant jar of whey protein isolate.
Cool, but is protein really all it’s cracked up to be?
Protein is absolutely needed by your body. It is recommended that you take in about 0.8 grams of protein per kilogram of body weight every day.  That is around 72 grams of protein for a person weighing 180 pounds.
So, that body bodybuilder is right; you do need to make sure you’re eating your protein, but make sure you’re eating your protein and not just drinking it from a jug.
Salmon, for instance is a great source of protein that also has omega-3 fatty acids; chicken breast, ham and steak are, too. All meats in general have very high amounts of protein.
Vegetarians needn’t be discouraged, however, because just one cup of lentils packs in 18 grams of protein. Just a few cups of lentils a day are all a person would need to get the recommended daily dose of protein. It is also important to mention that unlike steak or ham, lentils have almost no saturated fat or sodium. 
While steak is amazing tasting and loaded with protein—a 6-ounce serving has about 40 grams—it is also loaded with saturated fat. Diets high in saturated fat have been linked to chronic disease, specifically, coronary heart disease.
Ham is just as bad; consider that 6 ounces of ham has about 2,000 milligrams of sodium.
It really isn’t all that great to shovel in as much protein as you can. Protein needs to be absorbed by your body to have any positive effects. In order to make that process happen, your body releases acids which, in turn, make the body produce calcium to neutralize the acid.  If you eat massive amounts of protein without supplementing an extreme amount of calcium to balance that process out you could be forcing your body to take calcium away from other functions, like making strong bones and teeth.
Nice smiles or nice muscles?
You do need fatty acids, and because your body doesn’t make them naturally it is important to supplement through food.
The National Institutes of Health researched the effects of this important nutritional component and found that, “The polyunsaturated fatty acids alpha-linolenic acid (ALA) and linoleic acid (LA) must come from the diet because they cannot be made by the body.” 
There is a difference between omega-6 and -3 fatty acids, and it turns out that -3 is more important than -6. If you are a vegetarian, this may not be as concerning to you because your diet is likely loaded with great sources of omega-3s.
For the typical meat eater, however, you may be doing your body a disservice by being apathetic in understanding the difference between omega-3 and omega-6.
“Most American diets provide more than 10 times as much omega-6 than omega-3 fatty acids. There is general agreement that individuals should consume more omega-3 and less omega-6 fatty acids to promote good health. Good sources of ALA are leafy green vegetables, nuts, and vegetable oils such as canola, soy, and especially flaxseed. Good sources of EPA and DHA are fish and organ meats. LA is found in many foods, including meat, vegetable oils (e.g., safflower, sunflower, corn, soy), and processed foods made with these oils.” 
Sources: 1. Institute of Medicine, Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (Macronutrients). 2005, National Academies Press: Washington, DC. http://www.iom.edu/Reports/2002/Dietary-Reference-Intakes-for-Energy-Carbohydrate-Fiber-Fat-Fatty-Acids-Cholesterol-Protein-and-Amino-Acids.aspx
2. Agriculture, U.D.O., USDA Nutrient Database for Standard Reference, Release 14. 2005.