Hi,
If I was to stick to the portion sizes and frequency would that help me lose weight? What about  if someone wants to gain weight do they increase quantity or frequency?  I've never really paid attention to  the suggested amounts until now to be honest

I found that eating according to ALL suggestions, including exercise would help to drop weight.  Sorry to say I do not adhere to either.  I see focusing on beneficial foods as for dropping weight, or at least stay the same.

The diet can work either way.  To drop weight however moving more is most helpful.

In Swami (computer calculated) it is interesting to see how things change if one inputs eating larger or smaller portions.  But the BTD books also contain lower and upper limits if you do the calculations.  

To gain weight, sometimes it is more about foods that are more neutral, rather than beneficials.  Neutrals might build 'additional' calories.  

Depending on 'why' there is a need to gain weight, I would add calorie-dense foods rather than watery foods // beans rather than salad.

If it is for a belly, intestines that have suffered from illness then I would use soothing foods. The idea being= the less the body has to work to digest, the more strength it can use to absorb and gain strength.  ....  and then start moving more .. mom was ill a long time, but she used any time to exercise.  She used her cane by balancing it on her arms, fingers or knees, ankles, and built herself up, even while lying down.  

If you're following the portion sizes reccomended in the book,  be prepared to tweak things a little to get things "just right for you."  The portion size ranges in the book are there to accomodate people of all sizes- a 5' tall, 100 lb woman needs less food than a 6'6" tall 230 pound man!

I've always looked at the portion sizes as a guideline. I pay more attention to the ratios of the food groups than to the total numbers- all the diets contain far more vegetables and fewer grains than the "typical american diet" while the ratios of beans to animal protien vary depending on type.

In general, Os and Bs need to watch the carb portions to lose weight, while As and ABs need to keep the fat down to lose weight. That's a very broad statement, and there's plenty of individual variation (some A's need to keep the carbs down and some O's do poorly on high-fat diets) and everybody needs to keep their whole diets in balance (and "balance" will vary from person to person.)  But the general advice "focus on lean meats and veggies, more carefully control portion sizes of grains" is valid. Anybody trying to lose weight needs to keep sugar portions down- generally, about one teaspoon a day (or none) is all the added sugars you should be having.

I'm having to tweak things in my SWAMI to lose weight, namely cutting back on protein intake for fish and poultry.  You must watch the carbs and fats like a hawk, and stick with superfoods and mostly diamonds on those if possible.  I also don't exercise as much as SWAMI suggests, so it is indeed a balancing act according to who you are as an individual.  Once I found that balance, everything has worked out.