What is the fastest way to read vertex positions and indices into a buffer from a .obj file?

I've been making a program that displays 3D meshes using OpenGl. I tried loading a mesh with ~70,000 verticies and it took fairly long. I've simply been exporting my model from blender as an .obj and parsing it that way, but I was wondering if there was a better way since what I'm doing currently is pretty slow. For now, I'm not interested in anything but vertex positions and indices.

Is there a better file format for this? Or is it possible to optimize the code below? What is the industry standard for doing things like this? Should I just accept that it'll be slow no matter what?

Here is what I do to load the verticies and indicies. Currently, with a fairly large mesh with ~70,000 verticies, it takes ~1950ms (with \O2).

struct MeshData {    std::vector<float> vertexPositions;    std::vector<uint32_t> indicies;};MeshData VertexTest::parseObj(const char* path){    Timer t("Loading");    MeshData data;    std::ifstream stream(path);    std::string line;    srand(time(NULL));    while (std::getline(stream, line)) {        if (line[0] == 'v'&& line[1] == '') {            line = line.substr(2);            std::stringstream ss(line);            float num;            while (ss >> num) {                data.vertexPositions.push_back(num);            }            data.vertexPositions.push_back((float)rand() / (float)RAND_MAX);            data.vertexPositions.push_back((float)rand() / (float)RAND_MAX);            data.vertexPositions.push_back((float)rand() / (float)RAND_MAX);            data.vertexPositions.push_back(1.0f);        }        if (line[0] == 'f'&& line[1] == '') {            line = line.substr(2);            std::stringstream parse(line);            std::string section;            std::vector<int> temp;            while (std::getline(parse, section, '')) {                temp.push_back(std::stoi(section.substr(0, section.find('/'))) - 1);            }            if (temp.size() == 4) {                data.indicies.push_back(temp[0]);                data.indicies.push_back(temp[1]);                data.indicies.push_back(temp[2]);                data.indicies.push_back(temp[0]);                data.indicies.push_back(temp[2]);                data.indicies.push_back(temp[3]);            }            else if (temp.size() == 3) {                data.indicies.push_back(temp[0]);                data.indicies.push_back(temp[1]);                data.indicies.push_back(temp[2]);            }            else {                std::cout << "Unkown case: " << temp.size() << std::endl;                ASSERT(false);            }        }    }    return data;}